Will telephoto ever be viable on NEX?

Kiril Karaatanasov said:

Tom2572 said:

Kiril Karaatanasov said:

By the way EA2 is pretty good. It is better then A900 and A700 in terms of AF speed. In fact NEX with EA2 has more AF functionality then all Alpha cameras but A77 (may be A99 in the future). So A65, A57 etc. just do not stand up to NEX with EA2

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The a37, a57 and a65 all have a 15 point 3 cross type focusing systems which sounds the same as the LA-EA2, and my A57 focusing dots look exactly the same as the LA-EA2 attached to my NEX-3. Do you have something that says they are different because I was under the impression they were all the same?

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All NEX cameras have focus micro adjustment. I apologize for the rude statement but modern PDAF camera without this is not any good.

I liked A57 very much and thought of replacing my old A700 but lack of micro-adjustment is not acceptable.

Last Saturday I rented Zeiss 85/1.4. It focused well on NEX-7 with EA2 no adjustment needed, but if it needed it I had the tool. Unfortunate for me it had significant back focus on A700 - complete waste, I could not use it on A700 at all.

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D Cox said:

Why should a heavy lens have to be attached to a heavy camera? I can see no reason at all to add even more to the weight.

Nor do I see any particular reason why a long lens such as 400mm that is to be used with a NEX should be any smaller than one to be used on an SLR. It isn't going to make the optics better.

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• a trend to shrink camera bodies, but keeping quite sizable a sensor - the current industry's compromise in the form of APS-C one jumps to a fore immediately (X100, XP-1, NEX, Ricoh, Samsung);
• but the lenses are not as immensely shrinkable, a top IQ needs lots of good glass;
• so, a scheme involving a collapsible/foldable scope, coupled with a tiny body, but equipped with a good set of external controls + a streamlined, highly ergonomic grip, would seem like an interesting idea to retrieve from not so very remote past !!

IcyVeins said:

viking79 said:

IcyVeins said:

You don't think a 200-600mm equivalent f/4-5.6 is a good choice?

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When you use equivalents you have to do it for both aperture and focal length. A Panasonic 100-300 mm f/4-5.6 is equivalent to a 200-600 f/8-11. The only advantage is in length. A 300 mm is much shorter than a 600 mm.

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Wrong. It's only f/8 to f/11 for DOF purposes. Come on, do we really have to

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IcyVeins said:

play this stupid game with the equivalency police every time? In terms of

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forpetessake said:

forpetessake said:

Wrong. It's only f/8 to f/11 for DOF purposes. Come on, do we really have to

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Wrong, of course.

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forpetessake said:

IcyVeins said:

viking79 said:

IcyVeins said:

You don't think a 200-600mm equivalent f/4-5.6 is a good choice?

Click to expand...

When you use equivalents you have to do it for both aperture and focal length. A Panasonic 100-300 mm f/4-5.6 is equivalent to a 200-600 f/8-11. The only advantage is in length. A 300 mm is much shorter than a 600 mm.

Click to expand...

Wrong. It's only f/8 to f/11 for DOF purposes. Come on, do we really have to

Click to expand...

Wrong, of course. I wonder how many times it has to be repeated for some people to understand the simple physics behind the f-stop and various crop factors. Maybe some popular articles can help: http://www.clarkvision.com/articles/does.pixel.size.matter/#The_f_ratio_Myth

And this one is also pretty easy to understand: http://www.stanmooreastro.com/f_ratio_myth.htm

An equivalent lens on APS-C would be approx. 133-400 F/5.3-7.5, at taking into account a lot of losses and quick dimming at longer FL in such zooms (e.g. see dxo measurements), that lens would be like T-8.5. Can Sony make this equivalent lens? I don't doubt they can, but it's hardly anybody's dream. Same is true about other m4/3 lenses, as I mentioned before, the good lenses Olympus made were for 4/3 format, and those are big, heavy, and expensive, as one with knowledge of physics would reasonably expect.

forpetessake said:

play this stupid game with the equivalency police every time? In terms of

Click to expand...

as long as flat-earthers keep spreading their heresies, we have to correct them
http://forums.dpreview.com/forums/read.asp?forum=1041&message=42008062

Click to expand...

seachicken2000 said:

seachicken2000 said:

seachicken2000 said:

Wrong. It's only f/8 to f/11 for DOF purposes. Come on, do we really have to

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Wrong, of course.

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Agreed. In terms of the image you'll get, it's equivalent to f/8 at the wide end and f/11 at the long end.

At f/8 on full frame (and equivalently f/4 on m4/3) diffraction is starting to degrade the image. At f/11 it's doing even more damage, and probably explains the earlier poster's comment about these lenses being soft at the long end. Even wide open this lens is suffering.

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• actors : one Nex-7; and four MF-only lenses: one Zeiss 20/2.8, one Summicron R 35/2, one Elmarit R 100/2.8 APO, and one Sonnar 135/2.8;
• all lenses with mechanical apertures - and judging by their producers we can be sure mechanical accuracy is pretty good in each case;
• target : one flat, white, evenly lit surface;

• actions : set N7 to Av-mode, so the exposure meter will adjust SS; and set metering to spot;
• put the camera on tripos, set all lenses to infinity, but the tripod should be pretty close to the target's white surface, say 0.5 meter only; so all lenses are OOF;
• and then meter what shutter speeds should be, independently for each of four lenses mechanically preset to the same f/2.8 value;

• the results : with my lighting, and ISO 100... according to the camera the correct exposure in each case ought to be exactly 1/60 sec. - for each of four FLs in question;

• but... WAIT, isn't the equivalence say that this is entirely incorrect??

FuzzyQball said:

I think the answer is going to be a small sensor with high mp count and low noise that will allow the use of tiny lenses. Could be that 4/3rds might get there. They have a ways to go still to get to that point.

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• noise is not the main problem - although why to assume that a progress in m43 sensor technology will not be reflected in the APS-C one (perhaps to even greater degree)??
• the major issue with small[ish] sensors, like m43 and smaller, is an increasing difficulty (possibility even in many cases - vide 2.7x sensor of N1) in obtaining shallow OF;
• and as tiny lenses usually mean dark lenses , the degree of difficulty increases even more ;

FuzzyQball said:

You are right, but as Engineer, I have a lot of faith in technology continously improving. Will likely require a revolution in sensor technology.
--
Glenn

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Everdog said:

Ever shoot macros? With an M43 size sensor vs. APS, you have much more control over DoF.

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• when going to a forest for birding (and if lucky also for BIFs) my dream lens would be 400/2.8, or 500/4, light enough to allow free-hand shooting (the real life examples: EF 400/2.8L IS: http://www.the-digital-picture.com/Reviews/Canon-EF-400mm-f-2.8-L-IS-II-USM-Lens-Review.aspx or EF 500/4L IS: http://www.the-digital-picture.com/Reviews/Canon-EF-500mm-f-4-L-IS-II-USM-Lens-Review.aspx ;
• large opening is necessary, esp. if we'd like to put 2x TC on the former lens, or 1.4x on the latter (which will be then f/5.6);
• this would be an ideal , but alas in real life (esp. with advanced age looming closer and closer every year) we might need to settle for something more modest, say, like 400/5.6L;
• but even then ISO necessary for preserving high enough SS (which means at least 1/1000 sec, slightly less if supported on a branch or a tree trunk) will go as high as 1600 - just to allow relatively good IQ and low enough noise - even quite well lit forest is pretty dark usually;
• so... your solution of longish tele lens which is f/8-f/11 wide open doesn't seem to cut it ,

Schwaeble said:

Ignoring potential further advances in high refraction glass and aspherical compact lens element production technology, I don't know what could be done about shrinking high quality longer telephoto lenses other than i.e. going from a 400 or 500mm f4.5 lens to say a 500mm f8 or even f11 lens. At 16 to 24 megapixel APS-C sensors that's still below where diffraction starts hurting - or?

One thing that appears to be possible with advances in sensor technology is that todays IQ at say 400 ISO might be achieved with a sensor in two years at 800 ISO - give it another couple of years, then maybe even 1600 ISO. If advances in CF (or whatever hybrid) focussing keep up then such a lens could possibly be autocussed reliably, accurately and well (and maybe even quite well as maybe the masses to be moved around by whatever focussing motor are smaller, allowing faster moves, less strain, maybe more repeatability...) With those "dark" max apertures, then, would not such a lens offer at that time the same performance than today's f4.5 lens? Well, yes, of course except for DOF.

I never had such a long lens, so I don't really know how shallow one needs DOF to be at such a length. Personally, with lenses at the long end of what I use, I am more challenged with too little DOF.

Anyway, in the above scenario and if such a slow but good tele lens was price wise also much more affordable, lighter (those matter to me way more than size - for a tele lens) - as it should be - I might very well be interested. And that should be achievable with sensor advances not even a need for optical advances - or?

Disclaimer: I am probably not really spending enough time taking pictures to consider photography a legitimate hobby, which my explain some wilingness for compromises (just not really in IQ) that others may not be willing to accept. It certainly explains why heavy, high end, high $ long glass just is absolutely not for me. Does not mean so I would not want to have a long lens that would allow me to take high IQ images - just one that I care to afford and care to lug around...

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IcyVeins said:

forpetessake said:

IcyVeins said:

viking79 said:

IcyVeins said:

You don't think a 200-600mm equivalent f/4-5.6 is a good choice?

Click to expand...

When you use equivalents you have to do it for both aperture and focal length. A Panasonic 100-300 mm f/4-5.6 is equivalent to a 200-600 f/8-11. The only advantage is in length. A 300 mm is much shorter than a 600 mm.

Click to expand...

Wrong. It's only f/8 to f/11 for DOF purposes. Come on, do we really have to

Click to expand...

Wrong, of course. I wonder how many times it has to be repeated for some people to understand the simple physics behind the f-stop and various crop factors. Maybe some popular articles can help: http://www.clarkvision.com/articles/does.pixel.size.matter/#The_f_ratio_Myth

And this one is also pretty easy to understand: http://www.stanmooreastro.com/f_ratio_myth.htm

An equivalent lens on APS-C would be approx. 133-400 F/5.3-7.5, at taking into account a lot of losses and quick dimming at longer FL in such zooms (e.g. see dxo measurements), that lens would be like T-8.5. Can Sony make this equivalent lens? I don't doubt they can, but it's hardly anybody's dream. Same is true about other m4/3 lenses, as I mentioned before, the good lenses Olympus made were for 4/3 format, and those are big, heavy, and expensive, as one with knowledge of physics would reasonably expect.

IcyVeins said:

play this stupid game with the equivalency police every time? In terms of

Click to expand...

as long as flat-earthers keep spreading their heresies, we have to correct them
http://forums.dpreview.com/forums/read.asp?forum=1041&message=42008062

Click to expand...

You're just obfuscating here. Take a picture of something at f/4 on FF and f/4 on m4/3 at the same shutter speed and ISO, and they will both be lit the same, the only difference being that the m4/3 will get noisier faster as you increase the ISO, but at ISO 100 or 200 in the latest E-M5 sensor the photos will be pretty much identical except for the FF image offering a little bit better DR.

Or if you don't like that then take one picture at f/4 with a p&s and then take the same photo at f/22 with FF, and tell me which one is brighter...lol

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jpr2 said:

lets perform a very simple experiment;

• actors : one Nex-7; and four MF-only lenses: one Zeiss 20/2.8, one Summicron R 35/2, one Elmarit R 100/2.8 APO, and one Sonnar 135/2.8;
• all lenses with mechanical apertures - and judging by their producers we can be sure mechanical accuracy is pretty good in each case;
• target : one flat, white, evenly lit surface;

• actions : set N7 to Av-mode, so the exposure meter will adjust SS; and set metering to spot;
• put the camera on tripos, set all lenses to infinity, but the tripod should be pretty close to the target's white surface, say 0.5 meter only; so all lenses are OOF;
• and then meter what shutter speeds should be, independently for each of four lenses mechanically preset to the same f/2.8 value;

• the results : with my lighting, and ISO 100... according to the camera the correct exposure in each case ought to be exactly 1/60 sec. - for each of four FLs in question;

• but... WAIT, isn't the equivalence say that this is entirely incorrect??

jpr2
--
~
street candids (non-interactive):
http://www.flickriver.com/photos/qmusaget/sets/72157609618638319/
music and dance:
http://www.flickriver.com/photos/qmusaget/sets/72157600341265280/
B&W:
http://www.flickriver.com/photos/qmusaget/sets/72157623306407882/
wildlife & macro:
http://www.flickriver.com/photos/qmusaget/sets/72157600341377106/
interactive street:
http://www.flickriver.com/photos/qmusaget/sets/72157623181919323/

Comments and critique are always welcome!
~

Click to expand...

forpetessake said:

jpr2 said:

lets perform a very simple experiment;

• actors : one Nex-7; and four MF-only lenses: one Zeiss 20/2.8, one Summicron R 35/2, one Elmarit R 100/2.8 APO, and one Sonnar 135/2.8;
• all lenses with mechanical apertures - and judging by their producers we can be sure mechanical accuracy is pretty good in each case;
• target : one flat, white, evenly lit surface;

• actions : set N7 to Av-mode, so the exposure meter will adjust SS; and set metering to spot;
• put the camera on tripos, set all lenses to infinity, but the tripod should be pretty close to the target's white surface, say 0.5 meter only; so all lenses are OOF;
• and then meter what shutter speeds should be, independently for each of four lenses mechanically preset to the same f/2.8 value;

• the results : with my lighting, and ISO 100... according to the camera the correct exposure in each case ought to be exactly 1/60 sec. - for each of four FLs in question;

• but... WAIT, isn't the equivalence say that this is entirely incorrect??

Click to expand...

Click to expand...

jpr2 said:

• when going to a forest for birding (and if lucky also for BIFs) my dream lens would be 400/2.8, or 500/4, light enough to allow free-hand shooting (the real life examples: EF 400/2.8L IS: http://www.the-digital-picture.com/Reviews/Canon-EF-400mm-f-2.8-L-IS-II-USM-Lens-Review.aspx or EF 500/4L IS: http://www.the-digital-picture.com/Reviews/Canon-EF-500mm-f-4-L-IS-II-USM-Lens-Review.aspx ;
• large opening is necessary, esp. if we'd like to put 2x TC on the former lens, or 1.4x on the latter (which will be then f/5.6);
• this would be an ideal , but alas in real life (esp. with advanced age looming closer and closer every year) we might need to settle for something more modest, say, like 400/5.6L;
• but even then ISO necessary for preserving high enough SS (which means at least 1/1000 sec, slightly less if supported on a branch or a tree trunk) will go as high as 1600 - just to allow relatively good IQ and low enough noise - even quite well lit forest is pretty dark usually;
• so... your solution of longish tele lens which is f/8-f/11 wide open doesn't seem to cut it ,

jpr2

Schwaeble said:

Ignoring potential further advances in high refraction glass and aspherical compact lens element production technology, I don't know what could be done about shrinking high quality longer telephoto lenses other than i.e. going from a 400 or 500mm f4.5 lens to say a 500mm f8 or even f11 lens. At 16 to 24 megapixel APS-C sensors that's still below where diffraction starts hurting - or?

One thing that appears to be possible with advances in sensor technology is that todays IQ at say 400 ISO might be achieved with a sensor in two years at 800 ISO - give it another couple of years, then maybe even 1600 ISO. If advances in CF (or whatever hybrid) focussing keep up then such a lens could possibly be autocussed reliably, accurately and well (and maybe even quite well as maybe the masses to be moved around by whatever focussing motor are smaller, allowing faster moves, less strain, maybe more repeatability...) With those "dark" max apertures, then, would not such a lens offer at that time the same performance than today's f4.5 lens? Well, yes, of course except for DOF.

I never had such a long lens, so I don't really know how shallow one needs DOF to be at such a length. Personally, with lenses at the long end of what I use, I am more challenged with too little DOF.

Anyway, in the above scenario and if such a slow but good tele lens was price wise also much more affordable, lighter (those matter to me way more than size - for a tele lens) - as it should be - I might very well be interested. And that should be achievable with sensor advances not even a need for optical advances - or?

Disclaimer: I am probably not really spending enough time taking pictures to consider photography a legitimate hobby, which my explain some wilingness for compromises (just not really in IQ) that others may not be willing to accept. It certainly explains why heavy, high end, high $ long glass just is absolutely not for me. Does not mean so I would not want to have a long lens that would allow me to take high IQ images - just one that I care to afford and care to lug around...

Click to expand...

--
~
street candids (non-interactive):
http://www.flickriver.com/photos/qmusaget/sets/72157609618638319/
music and dance:
http://www.flickriver.com/photos/qmusaget/sets/72157600341265280/
B&W:
http://www.flickriver.com/photos/qmusaget/sets/72157623306407882/
wildlife & macro:
http://www.flickriver.com/photos/qmusaget/sets/72157600341377106/
interactive street:
http://www.flickriver.com/photos/qmusaget/sets/72157623181919323/

Comments and critique are always welcome!
~

Click to expand...