How could I know at which f-stop The HDR-A1 is shooting? at DVinfo.net

Vincent Sanchis · February 13th, 2006, 06:08 AM

Hi
I have been looking around to buy a new camera to jump in the HDV.
Since most of my work is documentary shooting I found that the small size of the HDR-A1 is very interesting, and its price is very good for a HDV camera.

However I am a bit concerned about its capabilities, due to my background as cinematographer.
Since Sony does not clarify it properly, I would like to know whether I would have enough manual control over this camera.
For example, I have understood that there is no manual control on the Iris, or to be more precised there is no information on the f-stop the camera is shooting.
Is it true?
Can it be fixed in some way?
What are you doing to control the f-stop at which it is working?
If it is true I think it will be useless for shooting a dramatic short or a feature film. Am I wrong?

Thanks for your help.

Alexander Karol · February 13th, 2006, 06:56 AM

Unfortunately, you can't. That is a really annoying thing about the HC1/A1. You can, however, see which f-stop setting was on during playback by enabling the DATA CODE option.

Someone has composed a chart for previous camcorders correlating each EXPOSURE notch with what f-stop/gain it sets the camcorder to. All I know is that at 6 notches from the right, the HC1/A1 has full aperture and 0 gain. Anything after that and gain is introduced.

Vincent Sanchis · February 13th, 2006, 09:54 AM

I think that those of us who have already purchased or are going to buy the A1 right now will be disapointing when Sony fixes (in a future model or revision of this one) this big mistake.
I'm sure this can be solved with a new firmware, maybe made by ourselves. But we have to wait at least 2 years, which is the guarantee given by Sony, at least in Europe.
At least for a camera which is sold as a 'Pro' model, one deserves to know at which f-stop is shooting.
The problem is that in this particular 'niche of market' (very small HDV 'pro' cameras) you have nothing else to choose. Otherwise Sony will fix this stupid problem, which in fact I'm almost sure is not a mistake, it's just the usual stupid and irritating Sony trick of protecting higher markets from lower markerts.
Sometimes I th¡nk that Sony deserves a sort of public demonstration, just to show them that we (their customers) are not stupid.
In the meantime. Those of you who are shooting dramatic movies, How do you deal with this problem?

Stu Holmes · February 13th, 2006, 10:03 AM

Agree with all of the above.

The only way to know what aperture the cam is using DURING recording is to become familiar with the exposure bar in Manual exposure mode.

In very dim conditions with cam at max. expsoure (i.e. 1/60th, f1.8, +18db gain) then the in manual mode the bar will be at full-right. Each click left will reduce gain by 3dB. So 6 clicks left, you're at 1/60th, f1.8, 0db).

In good light where the cam is not introducing gain at all, then fix the shutter speed at 1/60th (it is unlikely to go faster than this anyway unless it's VERY bright, but fix it just to be sure) and then shoot in manual mode. The exposure bar will then indicate aperture. You could mark the bottom of the LCD-screen surround to show what aperture corresponds with the position of the bar. As shutter is fixed, and 0gain due to bright light then it is adjusting only aperture.

Yes, it's a bit of a kludge, but it's this way or the highway.

Actually the only alternative, would be if you're shooting a movie and exverything is erady to go, record a 2second clip (shot all framed up), quick playback, see the aperture on the Data code, then back to TAPE mode and record away.
Neither method is wholly satisfactory i agree but that's the way it is.

Final thing, i'm fairly sure that one-click on the manual exposure bar corresponds to half a stop. I *think*...

Evan Donn · February 13th, 2006, 01:23 PM

here's a chart someone put together:

http://hdvforever.com/hdv/exposure/

I'm not sure the bit mapping theory/values are correct - his understanding of 'bits' seems incorrect to me, and some people have claimed there's an internal ND filter which is used to keep the camera at f4 whenever possible. Either way, it's a useful reference for determining your f-stop. I imagine you could just make a label for the edge of the screen which had these mapped out.

R.P. Cuenco · February 13th, 2006, 01:40 PM

according to the service manual's schematics, there is in fact an nd filter in both the hc1 and a1. as to it's strength and when exactly its activated, the manual doesnt say.

John Jay · February 13th, 2006, 02:03 PM

Here's a puzzle for ya

Shoot 1/50s or 1/60s according to territory and use auto exposure in low light conditions which bring about F1.8 18db, then hit the backlight button - everything gets brighter by about 1 stop but the display still reads F1.8 18db.

Try it

So where does that stop come from?

Stu Holmes · February 13th, 2006, 02:30 PM

it's been previously documented that the Sony Data code doesn't *always* tell the truth about the aperture. Certainly in previous cams this was sometimes the case. And i know as a previous poster said that some Sony cams use ND filters in the optical path, so that could be it, although i doubt it would have an internal ND filter in the path in low-light.

Note: In my earlier post, the 1/60th sec. shutter assumes we're talking abou NTSC cam. for PAL cam, equivalent figure is of course 1/50th sec.

R.P. Cuenco · February 13th, 2006, 03:46 PM

Quote:

Originally Posted by John Jay

Here's a puzzle for ya

Shoot 1/50s or 1/60s according to territory and use auto exposure in low light conditions which bring about F1.8 18db, then hit the backlight button - everything gets brighter by about 1 stop but the display still reads F1.8 18db.

Try it

So where does that stop come from?

couldnt it be altering the gamma curves? like, the inverse of cinegamma or some crazy solution that only sony could think of.

Tom Hardwick · February 14th, 2006, 05:06 AM

A good thread guys. The PDX10 did indeed utilise three internal (and undocumented) ND filters, but I was under the impression the A1's cmos chip was much more tolerant of exposure highs than the CCDs of old, and therefore didn't need ND.

I haven't had a close examination of the A1 but I'd suggest that the small cmos chip dimension (1.3") would necessitate ND intervention simply because of the degrading effect of diffraction at small apertures. No camera in the world is immune from this, but then Sony may well have stopped the aperture blades from closing beyond f/4.5 and simply used electronics to vary the exposure as it gets brighter, soaking the cmos output before the signal reaches the tape. This is cleverer and a whole lot cheaper and more reliable.

I'm with you when you all wince at the v'finder displays. The menus are all very clever on their little rolling drum. the touch screen offers all sorts of customisable changes to be made but just a minute, this is a CAMERA first and foremost, isn't it? The ancient TRV900 did better than this, keeping you informed as to the shutter speed, aperture, ND position and gain setting you'd selected, and telling the truth in replay, no less.

But what bugs me is the bottom loading (OK, it's whole lot slimmer than the PDX10 because of this design parameter) and the exposure lever. When shooting at a locked exposure there seems to be no way (unlike the Z1) where you can gently move the exposure up or down a wee bit. Every time you touch that little lever the exposure 'bumps' on screen - quite unacceptable.

Some people claim that ''Sony are not in tune with what serious film makers require in a video camera'', but Sony are not a company to make marketing mistakes, and they rightfully lead the world in digital video. They invent market niches, then blatantly divide and sub-divide such niches again and again to catch the punters.

Serious filmmakers want reliable, solid, tested camcorders that bring home
the goods, every time. If Sony don't make such cameras then I'm a monkey's uncle, and deserve to be painfully ram-raided.

The fact that many people out there have given Sony £1500 apiece shows the skill in Sony's marketing muscle. They knew they were buying bottom loading, single chip, slow start-up MPEG2 recording, touch screen and silly zoom control machines. Sony was hiding nothing from them, yet they went ahead and bought them.

Why? I'll tell you why. Because even with all these disadvantages the A1 is a milestone of camcorder quality that lifts it above the rest of the field by clear and very definite margins. You can spend the same sort of money very easily on a bog-standard DV cam from JVC, Panasonic and Canon, yet these guys didn't. They know why they didn't; they've written about it at length.

In short all their complaints are answered by simply spending more money.
Sony have indeed ''taken note'' The Z1 costs more and is more. Am I being harsh? Indeed I am. My Panasonic MX300 suffers a lot of the same design 'mistakes' such as bottom loading, poor screen visibility in good light, silly filter placement and so on. So why did I buy it? For the very same reasons people buy the A1. It's sharp, small, light and amazingly good value for money.

tom.

John Jay · February 14th, 2006, 10:15 AM

Even cheaper that that Tom; under 1000 green if you shop around :)

Fabulous performance with super slow zoom and the magic extra stop. Its even got a CA performance which outstrips the mighty black hedge trimmer.

Timew to get one in before the Tax year ends...

Tom Hardwick · February 14th, 2006, 10:23 AM

I agree, under 1k pretty easily (for the HC1, mind), but folk are buying these from Sony shops at 1.5k, which was my point John. They buy them with all the design compromises on board simply because the pictures are startlingly good. In automatic.

Vincent Sanchis · February 14th, 2006, 03:08 PM

I see that you accept all this 'compromises' mentioned above for a consumer camera (the HC1) which has a very low price in the USA.
However I'm talking about the A1E, which is a camera sold in Europe for about 2700 Euros ($ 3300 aprox). It's not a bargain, and besides Sony is selling this camera as a 'pro' model, and they are hidding all this 'compromises' to their customers.
In my opinion this is not 'fair-play'. When you buy a 'pro' camera, you deserved to have the most basic information (like the f-stop) offered in many consumer cameras.
I'm already investigating how to fix it via firmware. Unfortunately, I will not be able to start the 'tests' until the guaratee of the camera expires (two years in Europe).
If anyone successfully got it, please let us know.

Alexander Karol · February 14th, 2006, 03:29 PM

$3300 for a HDV professional camcorder is a bargain anywhere you go. Like you said however, it is somewhat "unacceptable" to not have gain/iris information in professional camcorders, but I know there are other reasons why SONY chose to do this. For example, for about $200-300 one can get the HDR-FX1 which has all the bells and whistles that professionals need. Now if all these features were available on the cheaper/smaller A1, who in their right mind would bank a little extra for the FX1? Nobody.

We aren't really "compromising" the fact that the A1 lacks this feature, we are accepting it. For us, A1 owners, the tradeoff between having such a feature and having HDV, XLR, DVCAM in a tiny body is a no-brainer.

Tom Hardwick · February 14th, 2006, 03:40 PM

The PDX10 was also sold as a 'pro camera' Vincent, and it suffered from appalling CCD smear and lack of viewfinder exposure information. On that camera you couldn't even trust the 'display' on tape replay either, yet Sony sold bucket loads of them. Why? because it was the first compact 16:9 that allowed you to use proper XLR mics, and even in automatic mode (ESPECIALLY in automatic mode) it gave great results in uneducated hands.

Sony decided not to have aperture readouts visible in the PDX10's 'finder because for most of the time the camera shoots at f/4.5 and exposure is varied by moving internal ND filters in and out of the light path. It didn't seem to hurt sales - they effectively sold the dull TRV950 to a whole new audience.

Sony marketing know their stuff. For the price of an ordinary SD Canon, JVC or Panasonic you can have a HiDef HC1. If you want XLRs, have the A1. Sony have covered all the exits, and they know it.

tom.

February 13th, 2006, 06:08 AM	#1
Vincent Sanchis New Boot Join Date: Dec 2005 Location: Oldenburg, Germany Posts: 23	How could I know at which f-stop The HDR-A1 is shooting? Hi I have been looking around to buy a new camera to jump in the HDV. Since most of my work is documentary shooting I found that the small size of the HDR-A1 is very interesting, and its price is very good for a HDV camera. However I am a bit concerned about its capabilities, due to my background as cinematographer. Since Sony does not clarify it properly, I would like to know whether I would have enough manual control over this camera. For example, I have understood that there is no manual control on the Iris, or to be more precised there is no information on the f-stop the camera is shooting. Is it true? Can it be fixed in some way? What are you doing to control the f-stop at which it is working? If it is true I think it will be useless for shooting a dramatic short or a feature film. Am I wrong? Thanks for your help.

February 13th, 2006, 01:40 PM	#6
R.P. Cuenco Regular Crew Join Date: Nov 2005 Location: Concord, CA Posts: 118	according to the service manual's schematics, there is in fact an nd filter in both the hc1 and a1. as to it's strength and when exactly its activated, the manual doesnt say. __________________ Letus35 Flip on HC1 FCP5 w/ Intel Mac Mini and Powerbook Ti G4

February 13th, 2006, 02:03 PM	#7
John Jay Major Player Join Date: Sep 2002 Location: US & THEM Posts: 827	the missing stop? Here's a puzzle for ya Shoot 1/50s or 1/60s according to territory and use auto exposure in low light conditions which bring about F1.8 18db, then hit the backlight button - everything gets brighter by about 1 stop but the display still reads F1.8 18db. Try it So where does that stop come from? __________________ John Jay Beware *PLUGGER-BYTES*

February 13th, 2006, 02:30 PM	#8
Stu Holmes Major Player Join Date: May 2005 Location: Europe Posts: 844	it's been previously documented that the Sony Data code doesn't always tell the truth about the aperture. Certainly in previous cams this was sometimes the case. And i know as a previous poster said that some Sony cams use ND filters in the optical path, so that could be it, although i doubt it would have an internal ND filter in the path in low-light. Note: In my earlier post, the 1/60th sec. shutter assumes we're talking abou NTSC cam. for PAL cam, equivalent figure is of course 1/50th sec. Last edited by Stu Holmes; February 14th, 2006 at 12:59 PM.

February 14th, 2006, 10:15 AM	#11
John Jay Major Player Join Date: Sep 2002 Location: US & THEM Posts: 827	Even cheaper that that Tom; under 1000 green if you shop around :) Fabulous performance with super slow zoom and the magic extra stop. Its even got a CA performance which outstrips the mighty black hedge trimmer. Timew to get one in before the Tax year ends... __________________ John Jay Beware *PLUGGER-BYTES*

February 13th, 2006, 06:56 AM	#2
Alexander Karol Regular Crew Join Date: Aug 2005 Location: Orlando, FL Posts: 198	Unfortunately, you can't. That is a really annoying thing about the HC1/A1. You can, however, see which f-stop setting was on during playback by enabling the DATA CODE option. Someone has composed a chart for previous camcorders correlating each EXPOSURE notch with what f-stop/gain it sets the camcorder to. All I know is that at 6 notches from the right, the HC1/A1 has full aperture and 0 gain. Anything after that and gain is introduced.

February 13th, 2006, 09:54 AM	#3
Vincent Sanchis New Boot Join Date: Dec 2005 Location: Oldenburg, Germany Posts: 23	I think that those of us who have already purchased or are going to buy the A1 right now will be disapointing when Sony fixes (in a future model or revision of this one) this big mistake. I'm sure this can be solved with a new firmware, maybe made by ourselves. But we have to wait at least 2 years, which is the guarantee given by Sony, at least in Europe. At least for a camera which is sold as a 'Pro' model, one deserves to know at which f-stop is shooting. The problem is that in this particular 'niche of market' (very small HDV 'pro' cameras) you have nothing else to choose. Otherwise Sony will fix this stupid problem, which in fact I'm almost sure is not a mistake, it's just the usual stupid and irritating Sony trick of protecting higher markets from lower markerts. Sometimes I th¡nk that Sony deserves a sort of public demonstration, just to show them that we (their customers) are not stupid. In the meantime. Those of you who are shooting dramatic movies, How do you deal with this problem?

February 13th, 2006, 10:03 AM	#4
Stu Holmes Major Player Join Date: May 2005 Location: Europe Posts: 844	Agree with all of the above. The only way to know what aperture the cam is using DURING recording is to become familiar with the exposure bar in Manual exposure mode. In very dim conditions with cam at max. expsoure (i.e. 1/60th, f1.8, +18db gain) then the in manual mode the bar will be at full-right. Each click left will reduce gain by 3dB. So 6 clicks left, you're at 1/60th, f1.8, 0db). In good light where the cam is not introducing gain at all, then fix the shutter speed at 1/60th (it is unlikely to go faster than this anyway unless it's VERY bright, but fix it just to be sure) and then shoot in manual mode. The exposure bar will then indicate aperture. You could mark the bottom of the LCD-screen surround to show what aperture corresponds with the position of the bar. As shutter is fixed, and 0gain due to bright light then it is adjusting only aperture. Yes, it's a bit of a kludge, but it's this way or the highway. Actually the only alternative, would be if you're shooting a movie and exverything is erady to go, record a 2second clip (shot all framed up), quick playback, see the aperture on the Data code, then back to TAPE mode and record away. Neither method is wholly satisfactory i agree but that's the way it is. Final thing, i'm fairly sure that one-click on the manual exposure bar corresponds to half a stop. I think...

February 13th, 2006, 01:23 PM	#5
Evan Donn Major Player Join Date: Feb 2006 Location: Philadelphia Posts: 795	here's a chart someone put together: http://hdvforever.com/hdv/exposure/ I'm not sure the bit mapping theory/values are correct - his understanding of 'bits' seems incorrect to me, and some people have claimed there's an internal ND filter which is used to keep the camera at f4 whenever possible. Either way, it's a useful reference for determining your f-stop. I imagine you could just make a label for the edge of the screen which had these mapped out.

February 14th, 2006, 05:06 AM	#10
Tom Hardwick Inner Circle Join Date: Mar 2003 Location: Billericay, England UK Posts: 4,711	A good thread guys. The PDX10 did indeed utilise three internal (and undocumented) ND filters, but I was under the impression the A1's cmos chip was much more tolerant of exposure highs than the CCDs of old, and therefore didn't need ND. I haven't had a close examination of the A1 but I'd suggest that the small cmos chip dimension (1.3") would necessitate ND intervention simply because of the degrading effect of diffraction at small apertures. No camera in the world is immune from this, but then Sony may well have stopped the aperture blades from closing beyond f/4.5 and simply used electronics to vary the exposure as it gets brighter, soaking the cmos output before the signal reaches the tape. This is cleverer and a whole lot cheaper and more reliable. I'm with you when you all wince at the v'finder displays. The menus are all very clever on their little rolling drum. the touch screen offers all sorts of customisable changes to be made but just a minute, this is a CAMERA first and foremost, isn't it? The ancient TRV900 did better than this, keeping you informed as to the shutter speed, aperture, ND position and gain setting you'd selected, and telling the truth in replay, no less. But what bugs me is the bottom loading (OK, it's whole lot slimmer than the PDX10 because of this design parameter) and the exposure lever. When shooting at a locked exposure there seems to be no way (unlike the Z1) where you can gently move the exposure up or down a wee bit. Every time you touch that little lever the exposure 'bumps' on screen - quite unacceptable. Some people claim that ''Sony are not in tune with what serious film makers require in a video camera'', but Sony are not a company to make marketing mistakes, and they rightfully lead the world in digital video. They invent market niches, then blatantly divide and sub-divide such niches again and again to catch the punters. Serious filmmakers want reliable, solid, tested camcorders that bring home the goods, every time. If Sony don't make such cameras then I'm a monkey's uncle, and deserve to be painfully ram-raided. The fact that many people out there have given Sony £1500 apiece shows the skill in Sony's marketing muscle. They knew they were buying bottom loading, single chip, slow start-up MPEG2 recording, touch screen and silly zoom control machines. Sony was hiding nothing from them, yet they went ahead and bought them. Why? I'll tell you why. Because even with all these disadvantages the A1 is a milestone of camcorder quality that lifts it above the rest of the field by clear and very definite margins. You can spend the same sort of money very easily on a bog-standard DV cam from JVC, Panasonic and Canon, yet these guys didn't. They know why they didn't; they've written about it at length. In short all their complaints are answered by simply spending more money. Sony have indeed ''taken note'' The Z1 costs more and is more. Am I being harsh? Indeed I am. My Panasonic MX300 suffers a lot of the same design 'mistakes' such as bottom loading, poor screen visibility in good light, silly filter placement and so on. So why did I buy it? For the very same reasons people buy the A1. It's sharp, small, light and amazingly good value for money. tom.

February 14th, 2006, 10:23 AM	#12
Tom Hardwick Inner Circle Join Date: Mar 2003 Location: Billericay, England UK Posts: 4,711	I agree, under 1k pretty easily (for the HC1, mind), but folk are buying these from Sony shops at 1.5k, which was my point John. They buy them with all the design compromises on board simply because the pictures are startlingly good. In automatic.

February 14th, 2006, 03:08 PM	#13
Vincent Sanchis New Boot Join Date: Dec 2005 Location: Oldenburg, Germany Posts: 23	I see that you accept all this 'compromises' mentioned above for a consumer camera (the HC1) which has a very low price in the USA. However I'm talking about the A1E, which is a camera sold in Europe for about 2700 Euros ($ 3300 aprox). It's not a bargain, and besides Sony is selling this camera as a 'pro' model, and they are hidding all this 'compromises' to their customers. In my opinion this is not 'fair-play'. When you buy a 'pro' camera, you deserved to have the most basic information (like the f-stop) offered in many consumer cameras. I'm already investigating how to fix it via firmware. Unfortunately, I will not be able to start the 'tests' until the guaratee of the camera expires (two years in Europe). If anyone successfully got it, please let us know.

February 14th, 2006, 03:29 PM	#14
Alexander Karol Regular Crew Join Date: Aug 2005 Location: Orlando, FL Posts: 198	$3300 for a HDV professional camcorder is a bargain anywhere you go. Like you said however, it is somewhat "unacceptable" to not have gain/iris information in professional camcorders, but I know there are other reasons why SONY chose to do this. For example, for about $200-300 one can get the HDR-FX1 which has all the bells and whistles that professionals need. Now if all these features were available on the cheaper/smaller A1, who in their right mind would bank a little extra for the FX1? Nobody. We aren't really "compromising" the fact that the A1 lacks this feature, we are accepting it. For us, A1 owners, the tradeoff between having such a feature and having HDV, XLR, DVCAM in a tiny body is a no-brainer.

February 14th, 2006, 03:40 PM	#15
Tom Hardwick Inner Circle Join Date: Mar 2003 Location: Billericay, England UK Posts: 4,711	The PDX10 was also sold as a 'pro camera' Vincent, and it suffered from appalling CCD smear and lack of viewfinder exposure information. On that camera you couldn't even trust the 'display' on tape replay either, yet Sony sold bucket loads of them. Why? because it was the first compact 16:9 that allowed you to use proper XLR mics, and even in automatic mode (ESPECIALLY in automatic mode) it gave great results in uneducated hands. Sony decided not to have aperture readouts visible in the PDX10's 'finder because for most of the time the camera shoots at f/4.5 and exposure is varied by moving internal ND filters in and out of the light path. It didn't seem to hurt sales - they effectively sold the dull TRV950 to a whole new audience. Sony marketing know their stuff. For the price of an ordinary SD Canon, JVC or Panasonic you can have a HiDef HC1. If you want XLRs, have the A1. Sony have covered all the exits, and they know it. tom.