Under-exposed images/Aperture and the FX1000/Lens ramping

Jeff Harper · January 14th, 2009, 03:49 AM

I admit the wide angle is very nice, Tom. I had forgotten how nice it was when I did use it especially in close quarters until you mentioned it.

Nice thing about the FX1000 now that I think about it, is how wide it is when full wide. In all of the times I've complained about the lens-ramping I have forgotten that on the flip side their is a significant benefit with how much you can fit in the shot with the cam compared to my old camera.

Tom Hardwick · January 14th, 2009, 04:03 AM

Quote:

Originally Posted by Martin Duffy

Gee I would have thought given we are now in 16:9 there would be no need for a wide angle lens.Also here's a dumb question but does a tele or wide lens that was once running on a 4:3 camera also work on a 16:9?Assuming so.

You assume correctly Martin - there's nothing special about the 16:9 format shape - it's just a wee bit wider than the old 4:3 that's all - so wide-angle and telephoto and anamorphic and close up lenses will all work just as well on your new wide-screen camera.

Thing is this 'wee bit wider' has nothing to do with how wide the lens sees - it only describes the aspect ratio. How wide the lens sees is down to the chip size and lens focal length.

The new Z5 has the wide-angle equivalent of a 29 mm lens. In camcorder terms this is pretty damn good, but in wide-angle terms it's just plain dull. Way back in the 70s a 28 mm lens was considered wide and a 20 mm lens was seen as super-wide.

So here we are 35 years later and we're nearly but not quite in the 'wide' ball park. So yes, I contend that you do indeed need a wide-angle converter, which means buying a 3 mm lens for your Z7. Not many of them about though.

tom.

Martin Duffy · February 14th, 2009, 03:31 AM

[QUOTE=Tom Hardwick;994301]I too have a very nice Canon 1.4x tele-extender for the Z1

Tom, would that Canon 1.4 you have work with the FX1000/Z5?

Regards

Martin

Tom Hardwick · February 15th, 2009, 02:52 PM

I don't see any reason why not Martin. The Z1, Z5, FX1000, FX1 and Z7 all share the 72 mm filter thread size.

Martin Duffy · February 15th, 2009, 04:03 PM

Quote:

Originally Posted by Tom Hardwick

I don't see any reason why not Martin. The Z1, Z5, FX1000, FX1 and Z7 all share the 72 mm filter thread size.

Tom, I thought I read somewhere on a thread that the new "G" lens system meant some convertor lens' were not matching up.

I may be wrong on this though. Hey, want to sell that Canon 1.4 Tom???!!!!!

Anyone tested the digital extender yet to see how the distortion factor is?

Jeff, As you also had a similar Panasonic like me, have you checked out the extender on the FX1000?

I found on the DVC62 it worked "OK" some days and then not so good on others. I mean sometimes the picture was a bit distorted but other times maybe in different light it wasn't so bad. I generally never used it as I had a Sony 1.4 that made a big difference with no loss in picture quality. Its a 43mm that I used on the TRV900 and I suspect it wouldn't work stepping up to 52mm and then to 72mm.

Tom, what are your thoughts on that? Using a 43mm stepping up to 72mm? Most likely to get a big ring around the edges I suspect?

Jeff Harper · February 15th, 2009, 04:49 PM

No Martin I never had an extender for the panasonic...sorry.

Martin Duffy · February 15th, 2009, 06:08 PM

Quote:

Originally Posted by Jeff Harper

No Martin I never had an extender for the panasonic...sorry.

Jeff, what I meant was that there is a button on the Panasonic "digital Zoom" that makes it extends the lens 1.25 or 1.5. Its on the play button but only accessible when the camera is in standy by.

On the FX1000 or Z5 this feature can be assigned to a button and is accessible even when the camera is in record.

It sort of makes the footage look like a 2 camera shoot which is pretty cool.

I know talking up using digital zoom will make many cringe but for me it may be useful.

Jeff Harper · February 19th, 2009, 02:06 AM

Martin, if the cam had it I never used it, sorry.

Stelios Christofides · February 19th, 2009, 04:37 AM

Hi guys

What does lens ramping mean? Does this have to do with Auto focus?

Stelios

Tom Hardwick · February 19th, 2009, 04:49 AM

Lens ramping is a term used to describe the lens' changing maximum aperture as you zoom.

To keep costs, weight and size down the zoom lens designer can opt to have the lens f/1.6 (say) at maximum wide-angle, but have a max of f/3.0 at full telephoto.

So with this lens if you're filming at max aperture at full wide, you'll need max aperture and +12dB of gain up at full tele to get the same exposure on your chips.

So beware. Camera manufacturers love to describe their lenses as '12x f/1.6 zoom', but most of them ramp lots (Panasonic 150) or much less (Sony Z7).

tom.

Tom Hardwick · February 19th, 2009, 04:52 AM

Quote:

Originally Posted by Martin Duffy

Tom, what are your thoughts on that? Using a 43mm stepping up to 72mm? Most likely to get a big ring around the edges I suspect?

If you're fitting a 43 mm lens onto a 72 mm camera filter thread, I'd say forget it. The other way around will be fine though.

Silas Barker · February 18th, 2010, 05:10 PM

Quote:

Originally Posted by Jeff Harper

It is a problem for sure Tim. It is so disappointing I'm sitting here totally dejected, I just bought my second FX1000, as you know. I would have tried using an FX1or Z1 with my first FX1000 if I had known about this.

I wonder if using an add-on lens would be useful? I don't understand optics very well, so I don't know. What does the signature of the one guy around here say? "Instructions? I just want to push buttons!" That sums me up pretty well, though I'm not proud of my lack of technical knowledge.

For today I have to work with what I have.

Hey Jeff, I have the Sony Z5 Camera which is much like the Fx1000. I just wondered about the same things your talking about and if you have found a solution. I also enjoy EXTREME close ups. There is no way to change the 20x zoom ramping effect. But if you used a lens tele adaptor would that work?

While the low light capability of the Z5 is better then the Z1 (even zoomed in all the way) it would be great to find a way to have more light still.

Let me know your thoughts and if you have found a solution,
Thanks!

Rob Morse · February 18th, 2010, 06:30 PM

If I have enough light, I will sometimes keep it at 3.4 so it stays consistent through the zoom. That way when you color correct or change the brightness in post, it stays level. Another way to correct the ramping, if you don't have enough light, is to gain up. You can set the gain switch from fast-middle-smooth. You can set the AGC level for the best picture and then set the gain to auto. Of course you would probably have to change those settings after the service. Auto is a good feature in certain situations, when used correctly that is. Finally, you can try the AE shift. It's a very slight adjustment but it does work. Like anything though, you need the correct setting for a specific environment.

The 20x lens is still better than the 12x when it's needed. As I mentioned elsewhere, sometimes it's the difference between getting that nice close-up or having to settle for a head and shoulder shot. I agree about the light, I always want a little more. In all fairness though, I can correct more in post than I could with the PD-170 (shooting in HDV).

Rob Morse · February 18th, 2010, 06:34 PM

Quote:

Originally Posted by Tom Hardwick

The new Z5 has the wide-angle equivalent of a 29 mm lens. In camcorder terms this is pretty damn good, but in wide-angle terms it's just plain dull. Way back in the 70s a 28 mm lens was considered wide and a 20 mm lens was seen as super-wide.

So here we are 35 years later and we're nearly but not quite in the 'wide' ball park. So yes, I contend that you do indeed need a wide-angle converter, which means buying a 3 mm lens for your Z7. Not many of them about though. tom.

I am coming to the realization that a wide angle lens is a must. Which one is the question.

Tom Hardwick · February 19th, 2010, 01:16 PM

Quote:

Originally Posted by Martin Duffy

Hey, want to sell that Canon 1.4 Tom???!!!!!

Yes, as a matter of fact I do Martin. But where are you? I'm in England, UK. This Canon C-8 tele 1.4x has a 67 mm attachment thread and I use it very successfully with a slim 67 > 72 adapter on the Z1. I also have a rectangular Cavision hood for it.

tom.

February 14th, 2009, 03:31 AM	#33
Martin Duffy Regular Crew Join Date: Jan 2006 Posts: 156	Need Tele lens for FX1000 [QUOTE=Tom Hardwick;994301]I too have a very nice Canon 1.4x tele-extender for the Z1 Tom, would that Canon 1.4 you have work with the FX1000/Z5? Regards Martin

February 19th, 2009, 04:37 AM	#39
Stelios Christofides Trustee Join Date: Jul 2003 Location: Nicosia, CYPRUS Posts: 1,080	Hi guys What does lens ramping mean? Does this have to do with Auto focus? Stelios __________________ My Blog: http://steliosc.blogspot.com "I hope for nothing, I fear nothing, I am free" Nikos Kazantzakis

January 14th, 2009, 03:49 AM	#31
Jeff Harper Inner Circle Join Date: Jun 2005 Location: Cincinnati, OH Posts: 8,425	I admit the wide angle is very nice, Tom. I had forgotten how nice it was when I did use it especially in close quarters until you mentioned it. Nice thing about the FX1000 now that I think about it, is how wide it is when full wide. In all of the times I've complained about the lens-ramping I have forgotten that on the flip side their is a significant benefit with how much you can fit in the shot with the cam compared to my old camera.

February 15th, 2009, 02:52 PM	#34
Tom Hardwick Inner Circle Join Date: Mar 2003 Location: Billericay, England UK Posts: 4,711	I don't see any reason why not Martin. The Z1, Z5, FX1000, FX1 and Z7 all share the 72 mm filter thread size.

February 15th, 2009, 04:49 PM	#36
Jeff Harper Inner Circle Join Date: Jun 2005 Location: Cincinnati, OH Posts: 8,425	No Martin I never had an extender for the panasonic...sorry.

February 19th, 2009, 02:06 AM	#38
Jeff Harper Inner Circle Join Date: Jun 2005 Location: Cincinnati, OH Posts: 8,425	Martin, if the cam had it I never used it, sorry.

February 19th, 2009, 04:49 AM	#40
Tom Hardwick Inner Circle Join Date: Mar 2003 Location: Billericay, England UK Posts: 4,711	Lens ramping is a term used to describe the lens' changing maximum aperture as you zoom. To keep costs, weight and size down the zoom lens designer can opt to have the lens f/1.6 (say) at maximum wide-angle, but have a max of f/3.0 at full telephoto. So with this lens if you're filming at max aperture at full wide, you'll need max aperture and +12dB of gain up at full tele to get the same exposure on your chips. So beware. Camera manufacturers love to describe their lenses as '12x f/1.6 zoom', but most of them ramp lots (Panasonic 150) or much less (Sony Z7). tom.

February 18th, 2010, 06:30 PM	#43
Rob Morse Major Player Join Date: Feb 2009 Location: Charlotte, NC Posts: 427	If I have enough light, I will sometimes keep it at 3.4 so it stays consistent through the zoom. That way when you color correct or change the brightness in post, it stays level. Another way to correct the ramping, if you don't have enough light, is to gain up. You can set the gain switch from fast-middle-smooth. You can set the AGC level for the best picture and then set the gain to auto. Of course you would probably have to change those settings after the service. Auto is a good feature in certain situations, when used correctly that is. Finally, you can try the AE shift. It's a very slight adjustment but it does work. Like anything though, you need the correct setting for a specific environment. The 20x lens is still better than the 12x when it's needed. As I mentioned elsewhere, sometimes it's the difference between getting that nice close-up or having to settle for a head and shoulder shot. I agree about the light, I always want a little more. In all fairness though, I can correct more in post than I could with the PD-170 (shooting in HDV).