Full frame lenses on aps-c, any +/-

amp · 12-24-2016, 09:02 PM

Just as the title says....I was curious if there were any advantages or disadvantages of mounting full frame lenses on aps-c cameras? Thanks in advance.

**boriscleto** · 12-24-2016, 09:28 PM - **1 Like**

Some will say that because an APS-C sensor is smaller that they will only use the sweet spot of the lens. Others will say that is a myth.

The primary disadvantage to using FF lenses on APS-C is size...

**lithedreamer** · 12-24-2016, 09:33 PM

Originally posted by boriscleto

The primary disadvantage to using FF lenses on APS-C is size...

Even then, there are lenses like the FA Limiteds which do great on APS-C while remaining small.

AussieTrev · 12-24-2016, 10:04 PM

Some of the older lenses are superb lenses, yes some are heavy, but as stated the limiteds are very compact. I use the FA 100 macro a lot which is large. Yet the D FA macro is very small and light and is a high quality lens.

amp · 12-24-2016, 10:06 PM

Originally posted by boriscleto

Some will say that because an APS-C sensor is smaller that they will only use the sweet spot of the lens. Others will say that is a myth.

The primary disadvantage to using FF lenses on APS-C is size...

If that happens to be the case, I may in fact consider more FF lenses for my k3.
Thanks

emalvick · 12-24-2016, 10:09 PM

Browse the galleries and lens Samples on this Web site. Most will be from aps-c as we've not had a ff very long in the pentax world.

Pentax ff lenses are generally small compared to other brands. Older ff lenses can have a disadvantage of being designed before digital, so lens flare and ca become problematic, but that has nothing to do with the sensor, and I find that issue easy to deal with.

**clackers** · 12-24-2016, 11:13 PM

Pentaxians have been enjoying full frame lenses on APS-C cameras for years, Amp. Many of them are small, too.

**UncleVanya** · 12-25-2016, 12:15 AM

Since only the central portion of the image circle is used it is likely that most full frame lenses have higher edge and corner performance when shot on apsc. This is not to imply that only the central glass is used to create the image - the exact physics aren't as important as the practical result.

**Quartermaster James** · 12-25-2016, 03:42 AM

Originally posted by emalvick

Browse the galleries and lens Samples on this Web site. Most will be from aps-c as we've not had a ff very long in the pentax world.

Weren't they all full frame before 2003? Seems there's only been about 13 years of APS-C lenses out of, what is it? 75-80 years.

**Rondec** · 12-25-2016, 04:24 AM - **1 Like**

The biggest positive to using full frame glass on APS-C is that you see less vignetting/better corner performance (since you aren't really seeing the corners) wide open. The biggest negative is that often focal lengths feel a little odd -- the FA 77 feels pretty long on a K3, just right on a K-1. A 24-70 doesn't feel quite wide enough for a walk around lens on APS-C and so on.

The biggest negative to using legacy glass in general is that purple fringing can be pretty bad. It is fixable in most cases, but there are times that fixing it leaves an odd gray out line around things.

MrB1 · 12-25-2016, 04:29 AM

Originally posted by UncleVanya

Since only the central portion of the image circle is used it is likely that most full frame lenses have higher edge and corner performance when shot on apsc. This is not to imply that only the central glass is used to create the image - the exact physics aren't as important as the practical result.

I agree, as I posted in another thread -

https://www.pentaxforums.com/forums/172-pentax-k-3/335623-if-you-were-allowed...ml#post3853850

Happy Christmas!
Philip

robthebloke · 12-25-2016, 06:07 AM - **1 Like**

The DA limiteds are fantastic lenses on apsc. The 15mm, 21mm, and 35mm macro are truly three of my favourite lenses I've ever used. When compared to the FA limiteds, well you would expect a lens costing 2 or 3 times the price to be better! Whilst I think most would agree that the rendering and larger apertures of the FA limiteds are big points in their favour, that does come at the expense of flare handling and some purple fringing.

To add to the confusion slightly, some DA lenses perform very well on FF - eg the DA*55, DA*200, DA*300; and to a lesser extent, the DA35 f2.4, DA50 f1.8, DA40, and DA70.

One of the disadvantages of FF glass is that it doesn't tend to go all that wide (for a reasonable price). The DFA15-30 is not cheap, and the FA31 is neither cheap, nor wide on apsc. If you're lucky, you might be able to locate a legacy sigma 12-24 that covers FF, but I'd still say the legacy SMC DA15 is probably the best wide angle lens for the k-3.

I'm not really a believer in all FF lenses being better than apsc glass. A good apsc lens is better than a bad FF lens. Read some reviews, look at images on Flickr, and if you like what you see, buy the lens.

photoptimist · 12-25-2016, 06:16 AM

There is one sure downside of FF on APS-C: Unless one replaces or adds a hood designed for APS-C, the extra light collected by an FF lens can create added flare on an APS-C camera relative to an APS-C lens. The sun may be out of the APS-C frame in the viewfinder but still in the FF frame of the lens and that extra light will be bouncing around inside the lens and mirror box.

In theory, if two optical designers were given the same budget for making lenses of the same focal length but one lens was FF and one was APS-C, the APS-C lens would be smaller, brighter, and sharper especially for shorter focal lengths -- it's simply much easier to create a bright aperture and sharp image over a smaller frame.

In practice, different lenses vary so much in design quality and manufacturing quality, that it's better to judge each lens on it's own. A good FF lens will work very well on APS-C.

**aslyfox** · 12-25-2016, 06:37 AM

My thoughts YMMV:

I admit to not being very knowledgeable on many things photography wise [hence my tag line: Seeker of Knowledge]

but one of the things i like about Pentax is that I still use some lens I inherited from my dad. it's a weird legacy thing to me.

This means primarily lenses designed for film and old Pentax SLRs.

If I am not mistaken, and I could be - please no public laughter - those would all be FF correct?

So, if I am right, i have new FF lenses as well as old FF lenses to choose from with the Pentax DSLR camera bodies.

**othar** · 12-25-2016, 06:45 AM

Originally posted by robthebloke

To add to the confusion slightly, some DA lenses perform very well on apsc - eg the DA*55, DA*200, DA*300; and to a lesser extent, the DA35 f2.4, DA50 f1.8, DA40, and DA70.

I think you ment perform well on FF here :-)

Originally posted by amp

I was curious if there were any advantages or disadvantages of mounting full frame lenses on aps-c cameras?

The designated lens hoods (if there are any) from the FF-lenses are too short for aps-c and therefore are not as effective on the smaller sensor as those of lenses designed for aps-c.
Because the image circle is designed for FF and not aps-c you might loose some contrast compared to DA lenses.
New lenses (so DA-lenses) have better coatings than the old ones.
A plus for FF-lenses on aps-c is you can use sensor shift without any restrictions.

That beeing said I shoot film from time to time and therefore own mainly FF-lenses for my K-3 and I was never disappointed with their performance.

12-24-2016, 09:02 PM	#1
amp Senior Member Join Date: Dec 2015 Posts: 168	Full frame lenses on aps-c, any +/- Just as the title says....I was curious if there were any advantages or disadvantages of mounting full frame lenses on aps-c cameras? Thanks in advance.

12-25-2016, 06:07 AM - 1 Like	#12
robthebloke Veteran Member Join Date: Sep 2013 Location: Sydney Photos: Albums Posts: 844	The DA limiteds are fantastic lenses on apsc. The 15mm, 21mm, and 35mm macro are truly three of my favourite lenses I've ever used. When compared to the FA limiteds, well you would expect a lens costing 2 or 3 times the price to be better! Whilst I think most would agree that the rendering and larger apertures of the FA limiteds are big points in their favour, that does come at the expense of flare handling and some purple fringing. To add to the confusion slightly, some DA lenses perform very well on FF - eg the DA55, DA200, DA300; and to a lesser extent, the DA35 f2.4, DA50 f1.8, DA40, and DA70. One of the disadvantages of FF glass is that it doesn't tend to go all that wide (for a reasonable price). The DFA15-30 is not cheap, and the FA31 is neither cheap, nor wide on apsc. If you're lucky, you might be able to locate a legacy sigma 12-24 that covers FF, but I'd still say the legacy SMC DA15 is probably the best wide angle lens for the k-3. I'm not really a believer in all FF lenses being better than apsc glass. A good apsc lens is better than a bad FF lens. Read some reviews, look at images on Flickr, and if you like what you see, buy the lens. Last edited by robthebloke; 12-25-2016 at 08:48 AM.*

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Full frame lenses on APS-C bodies	weaponx525	Pentax SLR Lens Discussion	37	02-13-2017 04:53 PM
Pentax 150-450mm review on full frame and APS-C	Alex-Nelson	Pentax SLR Lens Discussion	24	08-15-2016 01:49 AM
What happens when you put an aps-c lens on full frame(K-1)?	fstop18	Pentax Full Frame	8	04-13-2016 08:34 AM
Full Frame simulation on aps-c camera via ...	Pentaxtic	Pentax Full Frame	16	01-15-2014 05:06 PM
Lens hoods on full frame, APS-C...	nater	Pentax Camera and Field Accessories	4	08-04-2010 08:50 AM

12-24-2016, 09:28 PM - 1 Like	#2
boriscleto Loyal Site Supporter Join Date: Dec 2009 Location: North Syracuse, NY Photos: Gallery Posts: 16,475	Some will say that because an APS-C sensor is smaller that they will only use the sweet spot of the lens. Others will say that is a myth. The primary disadvantage to using FF lenses on APS-C is size...

12-24-2016, 09:33 PM	#3
lithedreamer Site Supporter Join Date: Sep 2013 Photos: Gallery \| Albums Posts: 1,799	Originally posted by boriscleto The primary disadvantage to using FF lenses on APS-C is size... Even then, there are lenses like the FA Limiteds which do great on APS-C while remaining small.

12-24-2016, 10:04 PM	#4
AussieTrev Veteran Member Join Date: Jul 2010 Location: Queensland Photos: Gallery \| Albums Posts: 3,590	Some of the older lenses are superb lenses, yes some are heavy, but as stated the limiteds are very compact. I use the FA 100 macro a lot which is large. Yet the D FA macro is very small and light and is a high quality lens.

12-24-2016, 10:06 PM	#5
amp Senior Member Join Date: Dec 2015 Posts: 168 Original Poster	Originally posted by boriscleto Some will say that because an APS-C sensor is smaller that they will only use the sweet spot of the lens. Others will say that is a myth. The primary disadvantage to using FF lenses on APS-C is size... If that happens to be the case, I may in fact consider more FF lenses for my k3. Thanks

12-24-2016, 10:09 PM	#6
emalvick Veteran Member Join Date: Feb 2008 Location: Davis, CA Photos: Gallery Posts: 1,642	Browse the galleries and lens Samples on this Web site. Most will be from aps-c as we've not had a ff very long in the pentax world. Pentax ff lenses are generally small compared to other brands. Older ff lenses can have a disadvantage of being designed before digital, so lens flare and ca become problematic, but that has nothing to do with the sensor, and I find that issue easy to deal with.

12-24-2016, 11:13 PM	#7
clackers Otis Memorial Pentaxian Join Date: Jul 2013 Location: Melbourne Photos: Albums Posts: 16,397	Pentaxians have been enjoying full frame lenses on APS-C cameras for years, Amp. Many of them are small, too.

12-25-2016, 12:15 AM	#8
UncleVanya Loyal Site Supporter Join Date: Jul 2014 Photos: Gallery \| Albums Posts: 28,404	Since only the central portion of the image circle is used it is likely that most full frame lenses have higher edge and corner performance when shot on apsc. This is not to imply that only the central glass is used to create the image - the exact physics aren't as important as the practical result.

12-25-2016, 03:42 AM	#9
Quartermaster James Loyal Site Supporter Join Date: Oct 2014 Location: Anchorage, Alaska Posts: 653	Originally posted by emalvick Browse the galleries and lens Samples on this Web site. Most will be from aps-c as we've not had a ff very long in the pentax world. Weren't they all full frame before 2003? Seems there's only been about 13 years of APS-C lenses out of, what is it? 75-80 years.

12-25-2016, 04:24 AM - 1 Like	#10
Rondec Loyal Site Supporter Join Date: Mar 2009 Location: Gladys, Virginia Photos: Gallery Posts: 27,653	The biggest positive to using full frame glass on APS-C is that you see less vignetting/better corner performance (since you aren't really seeing the corners) wide open. The biggest negative is that often focal lengths feel a little odd -- the FA 77 feels pretty long on a K3, just right on a K-1. A 24-70 doesn't feel quite wide enough for a walk around lens on APS-C and so on. The biggest negative to using legacy glass in general is that purple fringing can be pretty bad. It is fixable in most cases, but there are times that fixing it leaves an odd gray out line around things.

12-25-2016, 04:29 AM	#11
MrB1 Pentaxian Join Date: May 2013 Location: Hertfordshire, England Posts: 845	Originally posted by UncleVanya Since only the central portion of the image circle is used it is likely that most full frame lenses have higher edge and corner performance when shot on apsc. This is not to imply that only the central glass is used to create the image - the exact physics aren't as important as the practical result. I agree, as I posted in another thread - https://www.pentaxforums.com/forums/172-pentax-k-3/335623-if-you-were-allowed...ml#post3853850 Happy Christmas! Philip

12-25-2016, 06:16 AM	#13
photoptimist Pentaxian Join Date: Jul 2016 Photos: Albums Posts: 5,126	There is one sure downside of FF on APS-C: Unless one replaces or adds a hood designed for APS-C, the extra light collected by an FF lens can create added flare on an APS-C camera relative to an APS-C lens. The sun may be out of the APS-C frame in the viewfinder but still in the FF frame of the lens and that extra light will be bouncing around inside the lens and mirror box. In theory, if two optical designers were given the same budget for making lenses of the same focal length but one lens was FF and one was APS-C, the APS-C lens would be smaller, brighter, and sharper especially for shorter focal lengths -- it's simply much easier to create a bright aperture and sharp image over a smaller frame. In practice, different lenses vary so much in design quality and manufacturing quality, that it's better to judge each lens on it's own. A good FF lens will work very well on APS-C.

12-25-2016, 06:37 AM	#14
aslyfox Seeker of Knowledge Join Date: Aug 2016 Location: Topeka, Kansas Photos: Gallery \| Albums Posts: 24,581	My thoughts YMMV: I admit to not being very knowledgeable on many things photography wise [hence my tag line: Seeker of Knowledge] but one of the things i like about Pentax is that I still use some lens I inherited from my dad. it's a weird legacy thing to me. This means primarily lenses designed for film and old Pentax SLRs. If I am not mistaken, and I could be - please no public laughter - those would all be FF correct? So, if I am right, i have new FF lenses as well as old FF lenses to choose from with the Pentax DSLR camera bodies.

12-25-2016, 06:45 AM	#15
othar Site Supporter Join Date: May 2014 Location: Linz Photos: Albums Posts: 3,098	Originally posted by robthebloke To add to the confusion slightly, some DA lenses perform very well on apsc - eg the DA55, DA200, DA*300; and to a lesser extent, the DA35 f2.4, DA50 f1.8, DA40, and DA70. I think you ment perform well on FF here :-) Originally posted by amp I was curious if there were any advantages or disadvantages of mounting full frame lenses on aps-c cameras? The designated lens hoods (if there are any) from the FF-lenses are too short for aps-c and therefore are not as effective on the smaller sensor as those of lenses designed for aps-c. Because the image circle is designed for FF and not aps-c you might loose some contrast compared to DA lenses. New lenses (so DA-lenses) have better coatings than the old ones. A plus for FF-lenses on aps-c is you can use sensor shift without any restrictions. That beeing said I shoot film from time to time and therefore own mainly FF-lenses for my K-3 and I was never disappointed with their performance.