Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
03-22-2018, 08:20 AM   #1
Senior Member
antipattern's Avatar

Join Date: Apr 2012
Location: Berlin, Germany
Photos: Albums
Posts: 223
Lens test protocol for lens reviews and comparisons

After several flea market visits and buying lens collections, I have accumulated a lot of old glass. Some of these would make interesting reviews and comparisons, since I could directly compare different versions of the same lens (e.g. Lanthanum, Zebra and MC Pancolars; zebra, black and aluminium, and West-German Tessars) or a whole range of similar lenses. There is some rare glass in my collection as well, and it would be a shame to not test it properly before selling it on (or even keeping it).

Either way, I was thinking of doing some systematic lens reviews and coming up with a test battery that makes comparisons between lenses a bit easier.

What's important for you? What are good and not-so-good examples of reviews?

I quite like the reviews at Vintage Camera Lenses I don't intend to compete with them on sheer scale and number of lenses. I also found Vintage Lenses For Video quite a useful resource, particularly since I have been considering to do videos as well. I also like Kai W.'s gear reviews, even though I don't always find them informative.

Currently I have the following tests in mind:
  • Bokeh/Background - bokeh smoothness
  • Bokeh ball test using fairy lights at max aperture + stopped down
  • Portrait - probably with a stuffed animal as a model to keep it consistent
  • City/Landscape - just go out and shoot some examples
  • Flare (either sun or flashlight)
  • Handling + Usability
  • Sharpness - any way of doing this standardised without test charts?
  • Availability + Price

I could also put a summary of these reviews on Pentaxforums.

However, currently the time I could dedicate to such a project is rather limited. Also, I currently only have a Pentax K3 and no full frame camera available, and I think any lens tests would benefit greatly from using the lenses at the field of view they were made for. But I currently don't have the budget for a K1, particularly if I don't sell off any of my current lenses...

Either way, what do you think? What do you find useful? What makes a review interesting, what's annoying?

03-22-2018, 08:33 AM - 1 Like   #2
Pentaxian
normhead's Avatar

Join Date: Jun 2007
Location: Near Algonquin Park
Photos: Gallery | Albums
Posts: 36,686
QuoteOriginally posted by antipattern Quote
Either way, I was thinking of doing some systematic lens reviews and coming up with a test battery that makes comparisons between lenses a bit easier.

What's important for you? What are good and not-so-good examples of reviews?

Either way, what do you think? What do you find useful? What makes a review interesting, what's annoying?
I think you might be underestimating how much work this might be. As well, most people will only be interested in reviews of equipment they might be in the market for, so you've already lost quite a few people who might otherwise appreciate your tests.

What most people are looking for is comparison tests of currently available lenses. DA 55-300 PLM vs DA*60-250 vs DFA 70-200, vs DA*300 or DA*200. The trouble is, no one has all those lenses.

But, if it has hobby value for you , go for it.

why not start by posting a few reviews in the section in the forum? Personally, I find the anecdotal reports more valuable than the technical evaluation.

Pentax Lenses - Pentax Lens Reviews & Lens Database
03-22-2018, 08:40 AM - 3 Likes   #3
Veteran Member




Join Date: Dec 2010
Location: Ontario
Photos: Gallery
Posts: 3,332
It looks like you've got this covered, but the most important for me is consistency across a set of reviews. This gives a more meaningful comparison across the lenses reviewed, and if I happen to have a few lenses that a reviewer has covered it gives me a hands on basis of where they are coming from.

To make a review annoying to me, you could make it a video. Have just a talking head and no actual example photos. For bonus points, make sure the footage is shaky and uses rapid cuts as much as possible. Star wipes with whooshing noises are also aggravating.

edit- I'm talking reviews for stills photography. For video use like one of your links, sample video would seem a must
03-22-2018, 09:01 AM   #4
Site Supporter
Site Supporter




Join Date: May 2016
Photos: Albums
Posts: 1,580
I think it would be useful, because often you hear about old lenses but they don't get the same exposure/treatment as new ones. It would be good to add in some information about the full-frame performance, assuming you have a full-frame film camera, even if you don't do strict testing with full-frame.

03-22-2018, 09:23 AM - 1 Like   #5
Senior Member
antipattern's Avatar

Join Date: Apr 2012
Location: Berlin, Germany
Photos: Albums
Posts: 223
Original Poster
QuoteOriginally posted by normhead Quote
I think you might be underestimating how much work this might be. As well, most people will only be interested in reviews of equipment they might be in the market for, so you've already lost quite a few people who might otherwise appreciate your tests.
The time and effort involved do scare me a bit. But I also think that once I have a proper test battery and know what I'm doing I could be quite efficient.

QuoteOriginally posted by normhead Quote
What most people are looking for is comparison tests of currently available lenses
I'm afraid I wouldn't be of much use for that, though I might make a special about the Limiteds and I might include a D-FA 21 / 4 if such a thing (or similar) ever becomes available... :-)

---------- Post added Mar 22nd, 2018 at 09:37 ----------

QuoteOriginally posted by BrianR Quote
It looks like you've got this covered, but the most important for me is consistency across a set of reviews. This gives a more meaningful comparison across the lenses reviewed, and if I happen to have a few lenses that a reviewer has covered it gives me a hands on basis of where they are coming from.
QuoteOriginally posted by BrianR Quote
To make a review annoying to me, you could make it a video. Have just a talking head and no actual example photos. For bonus points, make sure the footage is shaky and uses rapid cuts as much as possible. Star wipes with whooshing noises are also aggravating.
My partner is a videographer, so she could comment on the usefulness for video as well. But I thought of doing a short summary videos. A brief introduction about the lens and maybe its history, a few shots of handling the lens (I think video could be useful here, too) and a few sample shots/videos. I'd keep it short, between 2.5-5 minutes only. I think if it's done well, it could be a good resource.

There's nothing worse than those rambling talking heads. Some of these videos go on for hours, and there's nothing but a guy rambling about FUD. They're terrible.

---------- Post added Mar 22nd, 2018 at 09:40 ----------

QuoteOriginally posted by leekil Quote
I think it would be useful, because often you hear about old lenses but they don't get the same exposure/treatment as new ones. It would be good to add in some information about the full-frame performance, assuming you have a full-frame film camera, even if you don't do strict testing with full-frame.
That's part of the problem... to test full frame I would have to sell a good chunk of lenses first, but then I'd have nothing more to test... chicken, eggs, can I get a K1 for Easter, please?


I added my first review to Pentaxforums, it looks like I'm a harsh reviewer:
Tokina AT-X 80-400mm F4.5-5.6 Lens Reviews - Tokina Lenses - Pentax Lens Review Database
03-22-2018, 09:41 AM   #6
Site Supporter
Site Supporter
pres589's Avatar

Join Date: Jan 2014
Location: Baltimore, MD
Photos: Albums
Posts: 3,341
I've been thinking about doing this for my own lens collection; I'm looking to get a good all-around manual zoom for a film kit I'm putting together and I figure I can help the community here by doing some reviews. About a sharpness test, I was planning on using a road map, one of those cheap fold-up jobs that you can buy at a gas station for very little money, and taping it to a wall. Set the focal length to a few key lengths, like 28, 35, 50, and 70mm and run it through four or five apertures at east stop. It's basically a big cheap test chart and they fold up small.

I'd also like to test coma by shooting into a tree with a lot of bare branches. That I'll do with a tripod aimed at the same tree from the same spot to try and reduce variance in testing.
03-22-2018, 10:22 AM   #7
Site Supporter
Site Supporter




Join Date: Mar 2008
Location: Prince George, BC
Photos: Gallery | Albums
Posts: 3,127
I would suggest the ultimate test for coma is an infinity shot of a star-filled night where any coma will render teardropped shaped stars at the edges of the frame.
03-22-2018, 10:46 AM   #8
Site Supporter
Site Supporter
pres589's Avatar

Join Date: Jan 2014
Location: Baltimore, MD
Photos: Albums
Posts: 3,341
Scratch that, I mean chromatic aberration, aka purple fringing. Maybe both are good to test for here, I don't know, at some point enough is enough.

03-22-2018, 12:26 PM - 1 Like   #9
Site Supporter
Site Supporter




Join Date: Nov 2012
Location: North Wales
Photos: Gallery | Albums
Posts: 2,364
How much work do you want to do?

This is what a diligent "technical" test, well presented, looks like:

Review: Minolta MD 50mm 1:1.2 | Minolta MD

Have to commend Tony for his efforts actually. Thats a lot of work. Another example of diligent work is Bengt Sandbergs - and he does film as well! Here's one of his reviews:

Helios-44-2 58mm f/2 (M42) Review


Bengt's reviews have the great merit of consistency. You can pull up reviews of different lenses and then the full sized pics of the same scene to compare. However although he covers the aperture range, and to some extent the zoom range with zooms, he doesn't cover the focus range, only posting images of the same landscape at infinity focus.

An alternative approach: a well informed "discursive" review like this:

Women and Dreams: Vivitar 200mm f/3 Series 1: Counterclockwise to Infinity

If you have some writing talent and would like to do a blog, well this could be the way to go. Here's another one with test charts:

Review: Vivitar (Komine) Series 1 200 mm f/3.0 Auto Telephoto – Vintage Lens Reviews

Personally I've not got into test charts, mainly because I don't have a convenient set up, but I have to say they can provide a more objective point of comparison (count those res lines), and highlight also aspects of fringing and contrast. As can brick walls - another item I don't have conveniently to hand.

My own efforts:
Test classic 70-210mm vintage lenses: vivitar series 1, tamron SP
A practical approach, based simply on taking pics! Select subjects to cover zoom range, focus range. Personally I can't be bothered to do every f stop, I can justify stopping at f11 by remarking thats when diffraction starts setting in on digital APSC. One of the learning points for me from this lens test is that it is the "extremities" that highlight the differences between the lenses: landscape at infinity, close focus. If you compare the flower pics for example all the lenses pretty much did similarly well.

For wide angle I like Dan Euritt's approach: an edge to edge crop of a landscape scene with lots of detail, used to create side by side composites. i've copied that approach on reviews I've posted here on PF.

http://www.codectest.com/2014/28mm-prime-lens-comparison-shot-on-sony-a7r-second-round

Couple more examples:

Studio test
Test of different 35mm lenses on APS-C sensor

A lot to be said for a studio test: consistent lighting (just no point in trying to compare lenses if the lighting you took the test pics in was substantially different), deliberate selection of subject(s) to highlight resolution, contrast, rendering etc. I don't have a studio or lights!

Bokeh test
42 Lens Mega Bokeh Test!

The thing for me from this one is that mosly they all look the same!

If there is one specific suggestion I have for you, it is: invest in a good lcd loupe. If there's one thing that can render your efforts and results worthless, it's focus errors. So use magnified live view with a loupe as the best you can do re focus on a pentax dslr with OVF! I assume you've got a good handle on the rest (stability ie tripods, bean bags; remote shutter with MLU etc).
Have fun.

Last edited by marcusBMG; 03-22-2018 at 01:32 PM.
03-28-2018, 05:37 AM   #10
Senior Member
antipattern's Avatar

Join Date: Apr 2012
Location: Berlin, Germany
Photos: Albums
Posts: 223
Original Poster
QuoteOriginally posted by marcusBMG Quote
How much work do you want to do?
Thanks, marcusBMG. These tests look fairly exhaustive and are quite interesting. I'm not sure I will have as much time to dwell into them into such depth. Maybe, once I have a basic protocol, it is possible to expand on it, step by step...
03-28-2018, 06:28 AM   #11
Seeker of Knowledge
Loyal Site Supporter
aslyfox's Avatar

Join Date: Aug 2016
Location: Topeka, Kansas
Photos: Gallery | Albums
Posts: 20,398
the only suggestion I can give to the OP and his lack of a full frame camera is to see if the OP could find a willing collaborator near by who has one and would help out.

if members with a K 1 near his locale would be willing they could PM the OP and see what could be worked out.

if all that would be necessary is to run the selected lens through a preplanned full frame photo test scheme perhaps the owner of the K 1 could meet up and the time necessary for the test shots would not be too long?

all analysis could be done after the test shots are collected by the OP after the owner of the K 1 has left

????
03-28-2018, 04:15 PM   #12
Des
Loyal Site Supporter
Loyal Site Supporter
Des's Avatar

Join Date: Jan 2014
Location: Sth Gippsland Victoria Australia
Photos: Albums
Posts: 4,892
QuoteOriginally posted by marcusBMG Quote
If there is one specific suggestion I have for you, it is: invest in a good lcd loupe. If there's one thing that can render your efforts and results worthless, it's focus errors. So use magnified live view with a loupe as the best you can do re focus on a pentax dslr with OVF!
Nice tip Marcus. Got any suggestions for a loupe?
03-28-2018, 04:39 PM - 2 Likes   #13
Veteran Member




Join Date: Jun 2012
Location: Tokyo
Photos: Gallery
Posts: 1,041
I am highly appreciated an effort like this. Thank you in advance and I am looking forward to see the test result.


QuoteOriginally posted by antipattern Quote
  • Flare (either sun or flashlight)

Since you plan to test lens flare, could you do it in a fashion that we can see starburst effect too?
not many lens test site doing / showing lens starburst effect.


For example: I like Cityscape photography, and to me, I would prefer my Cityscape / Landscape lenses to have nicer looking Starburst effect like in DA15 or 21 Green ring over smoother out of focus background like in the HD version. If I am unfamiliar with Pentax lenses, I would go for newer release like the HD and never know what I miss until it's too late.


03-29-2018, 05:59 AM - 1 Like   #14
Site Supporter
Site Supporter




Join Date: Nov 2012
Location: North Wales
Photos: Gallery | Albums
Posts: 2,364
QuoteOriginally posted by Des Quote
Nice tip Marcus. Got any suggestions for a loupe?
Well a large part of the benefit of using a loupe is the enclosure of the lcd cutting out all reflections and glare. Like most things you get what you pay for, the cheap ones are not very robust and tend to have inferior optics however for the sort of more occasional use we are discussing here (rather than eg video) they are likely to be sufficient. My needs were a bit more specific: I needed one with diopter adjustment. I managed to pick up a GGS Perfect for a good price off ebay (the good price somewhat offset by the need to acquire a mounting bracket for my K5). I've been pretty happy with this.
03-30-2018, 02:39 PM   #15
Des
Loyal Site Supporter
Loyal Site Supporter
Des's Avatar

Join Date: Jan 2014
Location: Sth Gippsland Victoria Australia
Photos: Albums
Posts: 4,892
QuoteOriginally posted by marcusBMG Quote
Well a large part of the benefit of using a loupe is the enclosure of the lcd cutting out all reflections and glare. Like most things you get what you pay for, the cheap ones are not very robust and tend to have inferior optics however for the sort of more occasional use we are discussing here (rather than eg video) they are likely to be sufficient. My needs were a bit more specific: I needed one with diopter adjustment. I managed to pick up a GGS Perfect for a good price off ebay (the good price somewhat offset by the need to acquire a mounting bracket for my K5). I've been pretty happy with this.
Thanks very much Marcus.
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!
bokeh, camera, comparison, comparisons, full-frame, head, k-mount, lens, lens review, lens reviews, lens test protocol, lenses, opinions, pentax lens, people, protocol for lens, review, reviews, slr lens, test, tests, time, tokina, video, vintage lenses
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
K-Mount digital pin protocol, power supply mjedlick Pentax SLR Lens Discussion 10 06-26-2016 01:09 PM
Pentax lens-body communication protocol snimcho Repairs and Warranty Service 15 06-25-2016 03:03 AM
Just Recieved K-1 from Adorama ! Is there a proper Protocol ? Dlanor Sekao Pentax K-1 24 06-23-2016 10:32 AM
Question What's the protocol for buying on PF? brightseal Site Suggestions and Help 15 01-20-2016 12:39 PM
Test: DxO K20D - full size comparisons falconeye Digital Processing, Software, and Printing 6 11-03-2009 03:42 PM



All times are GMT -7. The time now is 09:52 AM. | 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