View Full Version : 50mm Digital Zoom Test for Randy


Chris Harding
October 16th, 2013, 02:36 AM
Hey Randy

I used my Tamron 17-50 at full zoom on a few outdoor objects and also some indoor up to 15db gain and then did 2X digital zooms of all of them so you can compare the resolution with and without zoom.

Shot at 1080 50P so I had full res frame grabs.

Tell me what you think??

Chris

Noa Put
October 16th, 2013, 03:03 AM
I"m not Randy but just thought it would be good to say that these test photo's don't show the apparent resolution loss the digital zoom causes + the subjects are not that suitable for a clear view, it would be better if you choose a scene with more fine detail or patterns that are subject to causing moire, also fine print like text on books are a good way to see the difference. Best would be to first shoot the scene without DZ and then use the 2x DZ but move the camera back to get the same frame because then you can compare better.

Chris Harding
October 16th, 2013, 06:41 AM
Hi Noa

I did actually move back when I digitally zoomed in so didn't bother to be technically perfect regarding distance!! I think the only REALLY practical test would be inside a Church locked onto a bride and groom at the altar as that's what Randy wants to use the digital zoom for. Yes, I do agree that arifacts and moire will be amplified but not likely at a wedding ceremony unless the groom has a pinstriped suit!!

I looked carefully at the images side by side and the no digital zoom images are definitely a bit sharper than the digital zoom ones. Putting moire aside I think one might get away with using digital zoom especially if the end result was DVD....A little bit of sharpening in the NLE should suffice.

It certainly would be better if you simply don't have enough zoom apart from using the stock lens. I think I would prefer to use the Tamron 17-50 with some digital zoom and be able to stay at F2.8 rather than introduce noise when the stock lens has to zoom and only can manage F5.6 in a dingy Church!!!
It would be the lesser of two evils I think!!

Chris

Randy Johnson
October 16th, 2013, 10:36 AM
Chris,
Thanks for the test! I do seem some softness but I guess you need to consider the situation and reason for using it. Personally the way I think I may go is get a 85 mm at 1.4 for dark churches and use the digital zoom in that case some image loss will probably be that last of my worries:) the use something like a 17-50 no digital zoom at the reception. I can say I would never use digital zoom for higher end projects or ones where you have control over distance and lighting. Judging by those images even though they are a bit soft thats pretty good considering there zoomed all the way in.

Steven Digges
October 18th, 2013, 09:58 AM
I have been playing around with DZ and high gain settings lately because I have been trying to shoot an owl. There is a great horned owl that lands on top of a tall pine tree in my back yard once in a great while. It is an owl so of course it comes at night. Unlike Noa, who says he would never use DZ or 30 DB, I am glad they are there. Obviously we all try not to use them but sometimes they get the shot you could not otherwise get at all. And, I am trying to shoot the owl just for fun.

What I found is under perfect conditions like daylight I think the DZ is not to bad at all. I might use it on some real projects if I had to. When you start combining DZ with gain the image turns to crap in a hurry. I have the owl at 30 DB, DZ and underexposed because I lit him with a flashlight. It is absolute crap, especially when you underexpose. The other night I set the gain at 21 and opened the shutter to 1/30th, much better, of course. I am shooting at f2.8 with a Canon 70-200L.

Randy, your F1.4 and DZ plan for dark churches sounds sounds risky to me. I understand money matters. But, IMHO anyone charging for work and representing themselves as a pro should be properly equipped. It sounds to me like your compromises are setting you up for poor image quality. No offence intended.

Steve

Noa Put
October 18th, 2013, 01:34 PM
Once you have experienced the etc mode on the panasonic gh3 and g6 which magnifies 2,5 times you"ll find the digital zoom from Sony a joke, the differenc in image quality is big once zoomed in, the DZ from Sony is unique in the fact that you can perform a zoom with a prime lens though.

Randy Johnson
October 18th, 2013, 03:26 PM
Steven,
What would be a better plan? Are there any f1.4 lenses out there that are 100 to 200 mm?

Steven Digges
October 18th, 2013, 03:37 PM
Hi Randy,

Just about everybody makes a 70-200 F 2.8 fixed. They are expensive but worth it. There are tons of other lens options without counting on DZ. My point is the digital zoom combined with gain falls apart VERY quickly. The zoom magnifies the noise from the gain. You would be better off at 2.8 and gain when appropriate than you would be at F1.4 + gain + DZ.

Not to mention a magnified F1.4 gives you a scary DOF to shoot three people in a dark church.

Steve

Randy Johnson
October 18th, 2013, 04:41 PM
Well it looks nice but I think the weight may be a factor. 2.5 lbs.

Chris Harding
October 18th, 2013, 08:10 PM
Probably 99% of my weddings can be done on my stock zoom!! Maybe you are splitting hairs here. If you do need a big zoom then unless it's an underground dungeon F2.8 will be plenty to handle the interior! My rule is simple ..I go in with the stock zoom at the rehearsal and check out the lighting. AS long as the camera with a sample taken from where I will stand is comfortably under 21db gain then I just use the stock lens. If it wants to shift to 24db around an F4 zoom then most definitely the F2.8 zoom comes out to play.

I seriously doubt whether the Canon 70-200 at F2.8 won't easily handle most Churches and not push too much gain so if you shoot from the back as you say, then you might have to consider the Canon lens as an essential in your kit.

Remember, from where I shoot from in Churches (either aisle or left front pew) 50mm is more than enough zoom for me and it's actually more critical for me to be able to drop back to 17 or 18mm if the priest gets too close!

Chris

Randy Johnson
October 18th, 2013, 09:37 PM
Well I think what I may do is just get a Metabones nikon to NEX converter and a 17-50 or something like that and see how much I really need the longer lens if I find myself needing it I may pick one up. although back to my original plan can I assume that with the digital zoom the more you zoom in the softer the image gets? So if I used that 85 mm I would only find myself going all the way in in extreme situations.

Chris Harding
October 18th, 2013, 11:05 PM
Hi Randy

You did mention a while back that you shoot from near the rear of the Church? At worst I'm in the aisle normally at the 2nd pew from the front and to get a tight shot on the couple or on the person doing the readings, 50mm only just makes it so being at the back would need something a LOT bigger I would say.

My biggest issue with shooting further back was people in the pews tended to block my shot especially at Catholic weddings where they do the readings from a lectern/podium on normally the left so I make sure that I'm far enough forward so when I swing the main camera left to get a decent shot of the reader, I don't have the guy who is sitting in the front pew in my shot. With a 17-50 I would say your maximum distance from camera to subject cannot exceed 20' otherwise you will run out of zoom. Being pretty much up front is also the reason why I need the 17mm end of the lens too ...when the couple arrive, front and centre they are often no more than 10' away from me so I need to be pretty wide there.

My other reason for getting up front, apart from being blocked by guests, is if my wireless system DID fail on both lavs, I can still get usable audio from the on-camera mic which would never be possible if I was at the back!! I use a little GoPro at the back to get away from blocked shots and to get an overall Church view or I might even put it on a high stand up front so even photogs cannot block me and I have an alternate view if that happens.

Think carefully before you select a lens and base it on your normal position in a Church ... if I was at the back then something like a 24 -200 would be my choice ... you don't want to have to shoot the whole wedding with a 2X digital zoom especially if the light is low. The 17-50 works great for me as long as I'm up at the front.

Chris

Randy Johnson
October 20th, 2013, 01:39 PM
Just considering my options here but what do you think? As Chris has said and I agree the stock lens is fine for 80 to 90 percent of events I do its just in espcially dark churches I need to go to 24 db or higher so I was thinking instead of buying a few different lenses why not just get a metabone speed booster with a 18-200 lens if its 3.5-6 it will be more like 2.8-5.6 right? That extra stops should be all I need.

Steven Digges
October 20th, 2013, 01:53 PM
Sorry Randy,

The primary function of the speed booster is to be a lens adapter. They don't make one that goes from e-mount to e-mount. The fact that you can pick up an extra stop is a secondary benefit. And that is only with the speed booster. They make the same adapter without that benefit for $200.00 less.

Do you own a still camera with lenses for it? For example, a Metabones adapter has allowed me to put an entire collection of Canon lenses I already owned into service on my EA50. What a great benefit.

If you do not already own other lenses you would have to consider purchasing a lens to use the speed booster. Your kit lens won't work. Or, buy e-mount lenses, there is a ton of them. No adapter required.

Steve

Randy Johnson
October 20th, 2013, 04:23 PM
Well I was thinking of getting a lens like this.
Nikon AF-S NIKKOR 28-300mm f/3.5-5.6G ED VR Zoom Lens 2191 B&H
or this
Tamron 28-300mm f/3.5-6.3 XR Di VC LD Aspherical IF AF020NII-700

Chris Harding
October 20th, 2013, 05:56 PM
Hi Steve

Same with me. I have two Nikon still camera kits mainly for Realty work during the week and with a simple adapter (mine are Novoflex) I can use all my Nikon lenses on my EA-50's

I cannot see any huge advantage buying a zoom to 300mm ...especially for weddings I very much doubt whether one would need 300mm ...the camera already has a stock lens that's 18-200 and the same sort of speed as the ones Randy mentions. At 300mm you will have to have a brute of a tripod too cos any wobble will be greatly amplified up front.

I was lucky and had a photog mate who has a huge collection of Nikon lenses so I simply spend some time trying them on the EA-50 and seeing what worked best!!

Chris

Randy Johnson
October 20th, 2013, 07:57 PM
ok I guess I was thinking first of all with the metabones speed booster the Tameron would be more of a 18-250 ish and would be at 2.8-4.0 which would be enough light and wouldnt be that much heavier than what I have now. Am I wrong?How about this guy?
http://www.bhphotovideo.com/c/product/149629-USA/Canon_2562A002AA_EF_28_135mm_f_3_5_5_6_IS.html

Randy Johnson
October 22nd, 2013, 03:41 PM
Got some good news a photographer friend gave me a lens today, He was going to trash it because he couldnt use it anymore. Its a 80-200 @ 2.8 its a Nikon so all I need now is a adapter and maybe a 17-50. Also I need to figure out if I should put out the extra money for the speed booster and get the wider image or just get a regular adapter.

Steven Digges
October 23rd, 2013, 10:58 AM
Hey Randy,

It seems like your looking at everything except lenses that are made for your camera.

Check this one out if you have not already looked at it.

Sony E PZ 18-105mm f/4 G OSS Lens SELP18105G B&H Photo Video

It is a new release that is made for your camera. And it stays F4 from 18-105 MM

And it is a optical stabilized power zoom for $600.00 No adapter required.

Similar to what you have, yes, but better. At 105mm you will still be at f4 and it seems to me your objective here is to gain light when you need it. It think you will gain about two stops at 105mm over our kit lens. Does anyone know exactly what stop we are at with the kit lens at 105mm. I don't have time to look. F4 is not super bright but 2 stops is huge when you need it!

Steve

Edit: We posted at the same time. I did not see your Nikon post when I wrote this.

Randy Johnson
October 23rd, 2013, 02:43 PM
Steve,
I did see that lens and im considering it I like the fact that it is a lens for my camera. I am going to use the 80-200 for dark ceremonys and the stock lens for now. I am hoping that we may see more NEX lenses on the horrizon if not that Sony may be mine:) I wish it was at 2.8 though.

Chris Harding
October 23rd, 2013, 09:21 PM
Hi Guys

F2.8 for me really works well in low light situations. Steve I think the stock lens is only at F5 at around 100mm but F4 is F4 so that will be faster. At 105mm I'm doubting whether one would be needing a power zoom anyway so a manual lens and zoom is usually enough for me. You really only need to frame/re-frame ... I think the only time I seriously use the power zoom is during the signing where I can do a very slow zoom down to the document and then out again. With the EA-50 you are only likely to have to up the gain around 6db on the slower lens which is fine going from say, 15db to 21db BUT if you are at 21db or higher then it does become an issue.

Randy is your Nikon a constant F2.8 or not? They make an awesome 70 -200 zoom that's F2.8 thruout but it's pricey at over $2000!!!

Chris

Randy Johnson
October 24th, 2013, 06:49 AM
yes its a constant 2.8, Even though I dont "need" power zoom I still like the idea of a actual compatible lens. Auto Focus, full control etc. so I MAY get the 17-100 for receptions and keep the 80-200 for dark churches.

Tom Van den Berghe
February 5th, 2014, 03:01 PM
I just read this older post because I want to buy a extra lens for zoom. First I thought to buy the new powerzoom lens from sony with F4 aperture. But yesterday I tested again the stocklens in lower light and I found it better than I thought.So no need for the other powerzoom lens.

So the zoom reach of 11x will be mostly enough. So I was thinking of the tamron af sp 28-75mm f/2.8
On the nex -ea50 this will be a 50mm-110mm or something?

I have a eos to nex adapter so I better take a tamron for canon?
Works autofocus on the nex-ea50 with this lens?

Chris Harding
February 5th, 2014, 06:58 PM
Hi Tom

Even with the Metabones Smart Adapter III there are some lenses with a Canon mount like the Tamrons that actually don't communicate correctly with the EA-50 ..Check the post here on the Metabones to make sure yours will work.

Are you looking for a fast zoom then or a big range?? My Tamron 17-50 (also constant F2.8) is my favourite. Depends what you are shooting but at weddings I seldom need more than 50mm anyway as I normally work close. It's also my favourite Nikon still lens!!!

I had a 19mm Sigma e-Mount lens and the autofocus was poor .... You can always focus manually unless you are filming stuff with lots of motion/movement

Chris

Tom Van den Berghe
February 6th, 2014, 02:26 PM
Hi Chris,

I want a faster zoomlens than the stocklens. When the communion starts again within less then 3 months maybe the stocklens will be not fast enough.

About I filmed this test.This is bonus material for the dvd after it. The boy right is my son that will do his communion. So I also will film my own son that day in the church.

TOV on Vimeo

Filmed with the stocklens at 21db without zooming. It was dark that day in the church. So I'm afraid if the final day arrives and it will be again that dark, zooming with the stocklens will be impossible.

I hope you understand the situation. I only film 2 or 3 communions a year, never film weddings. Maybe if they ask me one day...

I also read here people uses old konica minolta lenses. I can find them really cheap second hand. You have LA-EA1/EA2 adapters for this and even much cheaper ones on ebay. Maybe I have to look for that? I really don't know.