Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
01-16-2014, 09:46 PM   #1
Loyal Site Supporter
GUB's Avatar

Join Date: Aug 2012
Location: Wanganui
Photos: Gallery | Albums
Posts: 2,524
Fringe killing the Q

I have just got a UV+IR cut filter and feel it is going to be a valuable addition when using good old legacy lens to help quieten CA a little.
There seem to be some debate on the forum about their usefulness but I havn't come across any objective comparisons so I thought I would upload my preliminary tests-- rough as they are.
I would love to have some input from anyone using these filters.
First up is showing that the filter is indeed doing its job at the infrared end.
Then an assembly of 200 x 200 pixel crops of the worst CA I could create with and without the filter. While the result is by no means definitive you can see some heat is taken out of the red end.
Then a couple of comparison crops (1000x 750) showing quite a significant difference through haze.
I was surprised how much the Q 01 lens responded to the filter.
Remember that the Q has no anti aliasing filter so the lens is the only barrier to the invisible end of spectrum rays.
I suspect the lens glass does a good job of stopping UV but the infrared is passing through.
That is why there is more of a response at the red end
Once more I would love some input from anyone using these filters.

Attached Images
     
01-16-2014, 11:52 PM   #2
Veteran Member
Billy Joe's Avatar

Join Date: Jun 2013
Posts: 316
Don't mean to sound dumb, but I am not sure what I am looking at here.

But either way the PF/CA on those lenses really look bad, filter or no filter. I would never use anything that gave me that much PF to try and deal with in post production.
01-17-2014, 12:21 AM   #3
GUB
Loyal Site Supporter
GUB's Avatar

Join Date: Aug 2012
Location: Wanganui
Photos: Gallery | Albums
Posts: 2,524
Original Poster
QuoteOriginally posted by Billy Joe Quote
Don't mean to sound dumb, but I am not sure what I am looking at here.

But either way the PF/CA on those lenses really look bad, filter or no filter. I would never use anything that gave me that much PF to try and deal with in post production.
Remember they are small, 200pixel crops, (ie 0.003 of the sensor) taken of an image chosen to maximize CA. And the lens is wide open. So the result is intended to be about as bad as you can get so any improvement can be seen.
01-17-2014, 01:09 AM   #4
Inactive Account




Join Date: Oct 2011
Posts: 147
Minimizing PF/CA on Q Adapted Lenses

Interesting PF solution...

Not intending to hijack this thread, but perhaps others have made specific recommendations on legacy M42 lens that have little PF/CA on Q in the first place? Threads? URLs?

I ran an unscientific wide-open comparison on my Q with a Tak 50mm F1.4, 55mm 1.8, 55mm 2.0 and Macro Tak 50mm F4.0. The Macro Tak performed definitely best with the least PF. The other three were not far apart between them - with the 55mm F2.0 perhaps slightly better of those three.

Haven't tried it yet - but I plan to dig out my old Macro Tak 100mm F4.0 and see how well it works as a 560mm on the Q... Hopefully...

01-17-2014, 01:17 AM   #5
GUB
Loyal Site Supporter
GUB's Avatar

Join Date: Aug 2012
Location: Wanganui
Photos: Gallery | Albums
Posts: 2,524
Original Poster
QuoteOriginally posted by cahudson42 Quote
Interesting PF solution...

Not intending to hijack this thread, but perhaps others have made specific recommendations on legacy M42 lens that have little PF/CA on Q in the first place? Threads? URLs?

I ran an unscientific wide-open comparison on my Q with a Tak 50mm F1.4, 55mm 1.8, 55mm 2.0 and Macro Tak 50mm F4.0. The Macro Tak performed definitely best with the least PF. The other three were not far apart between them - with the 55mm F2.0 perhaps slightly better of those three.

Haven't tried it yet - but I plan to dig out my old Macro Tak 100mm F4.0 and see how well it works as a 560mm on the Q... Hopefully...
Nice one. I am just packing up for a weekend tramp and wondering which old lens to take to companion the Q and 01. The 50mm macro tak f4 it is
01-17-2014, 04:28 AM   #6
Pentaxian
Transit's Avatar

Join Date: Aug 2007
Location: Whanganui NZ
Photos: Gallery | Albums
Posts: 4,075
Nice display Gub
I reckon the winner for most improved is the 01 !
Will try the filter on my 1.2 tomorrow
01-17-2014, 05:20 AM   #7
Junior Member




Join Date: Jul 2008
Posts: 41
Takes care of one of my biggest concerns with the Q.

Is this the original Q? Does the Q7 do better than original/Q10 for purple fringe?
01-17-2014, 10:19 AM   #8
GUB
Loyal Site Supporter
GUB's Avatar

Join Date: Aug 2012
Location: Wanganui
Photos: Gallery | Albums
Posts: 2,524
Original Poster
QuoteOriginally posted by bdp1 Quote
Takes care of one of my biggest concerns with the Q.

Is this the original Q? Does the Q7 do better than original/Q10 for purple fringe?
This is the original Q
If the Q7 doesn't have an anti aliasing filter then it is probably much the same with old glass.

01-17-2014, 11:12 AM   #9
Veteran Member
Billy Joe's Avatar

Join Date: Jun 2013
Posts: 316
QuoteOriginally posted by GUB Quote
This is the original Q
If the Q7 doesn't have an anti aliasing filter then it is probably much the same with old glass.
So are saying the K5llS and K-3 - without AA filters will be this bad with all my old lenses? I was thinking of upgrading, but I shoot old glass way more than new... I certainly dont want to deal with that much PF/CA every time
01-17-2014, 11:15 AM   #10
Veteran Member
crewl1's Avatar

Join Date: Jul 2010
Location: Los Angeles, CA
Photos: Gallery | Albums
Posts: 9,797
QuoteOriginally posted by cahudson42 Quote
Interesting PF solution...

Not intending to hijack this thread, but perhaps others have made specific recommendations on legacy M42 lens that have little PF/CA on Q in the first place? Threads? URLs?

I ran an unscientific wide-open comparison on my Q with a Tak 50mm F1.4, 55mm 1.8, 55mm 2.0 and Macro Tak 50mm F4.0. The Macro Tak performed definitely best with the least PF. The other three were not far apart between them - with the 55mm F2.0 perhaps slightly better of those three.

Haven't tried it yet - but I plan to dig out my old Macro Tak 100mm F4.0 and see how well it works as a 560mm on the Q... Hopefully...
If you haven't done so already, please add your samples and observations to the adapted lenses index thread at the top of this forum.
Thanks!
01-17-2014, 11:18 AM   #11
Veteran Member
crewl1's Avatar

Join Date: Jul 2010
Location: Los Angeles, CA
Photos: Gallery | Albums
Posts: 9,797
QuoteOriginally posted by Billy Joe Quote
So are saying the K5llS and K-3 - without AA filters will be this bad with all my old lenses? I was thinking of upgrading, but I shoot old glass way more than new... I certainly dont want to deal with that much PF/CA every time
The issue with the Q is that the pixels are densely packed in a tiny area, so any PF CA looks worse as it is shown on more pixels.
On the K-5 it will be easier to correct in post since the number of pixels showing the PF/CA is smaller.
01-18-2014, 08:00 PM   #12
Pentaxian
ScooterMaxi Jim's Avatar

Join Date: Jul 2009
Location: Minnesota
Posts: 1,501
QuoteOriginally posted by GUB Quote
I have just got a UV+IR cut filter and feel it is going to be a valuable addition when using good old legacy lens to help quieten CA a little.
There seem to be some debate on the forum about their usefulness but I havn't come across any objective comparisons so I thought I would upload my preliminary tests-- rough as they are.
I would love to have some input from anyone using these filters.
First up is showing that the filter is indeed doing its job at the infrared end.
Then an assembly of 200 x 200 pixel crops of the worst CA I could create with and without the filter. While the result is by no means definitive you can see some heat is taken out of the red end.
Then a couple of comparison crops (1000x 750) showing quite a significant difference through haze.
I was surprised how much the Q 01 lens responded to the filter.
Remember that the Q has no anti aliasing filter so the lens is the only barrier to the invisible end of spectrum rays.
I suspect the lens glass does a good job of stopping UV but the infrared is passing through.
That is why there is more of a response at the red end
Once more I would love some input from anyone using these filters.
Great to see that a filter can give you so much relief. However...

I have the m200 f/4 and would never ever shoot at f/4 on a regular camera, let alone tortured on the Q. The same vintage 75-150 was a much sharper lens at the same f/stop, but still requires stop down.

I sold the 40mm in the '70s - and it was an interesting novelty as a pancake, but easily the dullest tool to be found among standard primes. These really are lenses not to be mounted on a Q, but many vintage lenses do perform very well with very little need for adjustment (although RAWs need to be sharpened). Of course, the 01 is a very fine tool - so you really are exhibiting both ends of the prime spectrum here.
01-20-2014, 12:44 AM   #13
GUB
Loyal Site Supporter
GUB's Avatar

Join Date: Aug 2012
Location: Wanganui
Photos: Gallery | Albums
Posts: 2,524
Original Poster
QuoteOriginally posted by Billy Joe Quote
So are saying the K5llS and K-3 - without AA filters will be this bad with all my old lenses? I was thinking of upgrading, but I shoot old glass way more than new... I certainly dont want to deal with that much PF/CA every time
The Pixels of the Q are one third the size of my K30s ones but my gut feeling is that the CA is more than 3 times as bad. Maybe it is because it is the lack of an AA filter or maybe it is an optical phenomena of straining the hell out of an old lens. I have been comparing my various lens on the K30 while waiting for the Q so as to know which ones to persevere with. The strange thing is they all tended to out-perform my DAL55-300 at wider apertures but it caught up when stopped down a bit. But on the Q it seems to be winning hands down. That is what led me to think it may be a coating issue, perhaps with the later coatings having a similar effect as a cut filter.
01-20-2014, 07:19 AM   #14
Inactive Account




Join Date: Oct 2011
Posts: 147
Least PF/CA Legacy Lenses on Q

The legacy M42 lenses I have found to give the least PF/CA on my Q are the Super-Multi-Coated Macro Takumar 50mm F4.0 (best) and now (just tried it) the 100mm version - Super-Multi-Coated Macro Takumar 100mm F4.0 (not far behind).

While F4.0 looks good to me on both lenses, F5.6 is an improvement.

Except for the original Q 5-15mm 02, I have no other 'modern' DA* or other lenses to compare with. Sorry. I shoot all manual M42s on my K-01, and same on Q (excepting the 02).

Were you able to try the 50mm Macro-Tak on your trip? Not good?? Compared to DAL 55-300?
01-21-2014, 12:06 AM   #15
GUB
Loyal Site Supporter
GUB's Avatar

Join Date: Aug 2012
Location: Wanganui
Photos: Gallery | Albums
Posts: 2,524
Original Poster
QuoteOriginally posted by cahudson42 Quote
The legacy M42 lenses I have found to give the least PF/CA on my Q are the Super-Multi-Coated Macro Takumar 50mm F4.0 (best) and now (just tried it) the 100mm version - Super-Multi-Coated Macro Takumar 100mm F4.0 (not far behind).

While F4.0 looks good to me on both lenses, F5.6 is an improvement.

Except for the original Q 5-15mm 02, I have no other 'modern' DA* or other lenses to compare with. Sorry. I shoot all manual M42s on my K-01, and same on Q (excepting the 02).

Were you able to try the 50mm Macro-Tak on your trip? Not good?? Compared to DAL 55-300?
Yes I tried the M42 S-M-C 50mm macro and was quite pleased with it. It looks a little soft of course running alongside the 8.5mm. But no major CA . I think the filter sharpens sunset type horizons a little. The image is jpg saved sharpness at hard and no further sharpening. ISO 800 1/250sec and probably stopped to 5.6. It is not intended to be a test image but I would expect to see some CA in the tree silhouettes if it was present.
I find the 8.5 fringes at the edges wide open.It looks like CA from the blue end of the spectrum and the filter does not do much to remove it.
Attached Images
View Picture EXIF
PENTAX Q  Photo 
View Picture EXIF
PENTAX Q  Photo 
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
camera, crops, filter, filters, input, job, lens, mirrorless, pentax q, pentax q10, pentax q7, q10, q7
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
The ultimate weekend warrior killing me! fizzyhair General Talk 16 09-10-2012 02:55 PM
The killing of OBL: stevewig General Talk 148 05-24-2011 01:35 PM
People SA Pentaxians at the Fringe Parade UltraWide Post Your Photos! 16 02-27-2010 07:29 PM
Attack of the Purple Fringe 8540tomg Post Your Photos! 12 07-26-2009 07:46 PM
The Good Times are Killing Me brkl Post Your Photos! 7 03-09-2009 12:53 PM



All times are GMT -7. The time now is 09:38 PM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top