Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
02-05-2017, 09:56 PM   #1
Senior Member
65535's Avatar

Join Date: Dec 2008
Location: Canada
Posts: 187
Basic question - Macro lens length differences?

I see 35mm, 50mm, 100mm macro lenses. What is the difference in the kind of pictures they produce?

Does 100mm mean more magnification?

02-05-2017, 10:00 PM - 1 Like   #2
Loyal Site Supporter
Loyal Site Supporter
UncleVanya's Avatar

Join Date: Jul 2014
Photos: Gallery | Albums
Posts: 28,064
Same 1:1 ratio of reproduction. The difference is based on the perspective afforded by the working distance. There are some threads and some comparisons. Insects = use the 100 typically for the extra distance. Flowers = matter if choice of perspective 35,50,or 100. Coins and similar longer gives easier lighting angles.
02-05-2017, 10:57 PM   #3
Site Supporter
Site Supporter
Digitalis's Avatar

Join Date: Mar 2009
Location: Melbourne, Victoria
Photos: Gallery
Posts: 11,694
QuoteOriginally posted by UncleVanya Quote
The difference is based on the perspective afforded by the working distance
Working distance = the distance between you and your subjects. A 35mm macro at 1:1 has less working distance than a 100mm macro lens at 1:1

There are also some noticeable differences in compression, longer macro lenses compress distances more than wide angle ones. This becomes important as the subject magnification goes up.
02-05-2017, 11:07 PM - 1 Like   #4
Loyal Site Supporter
Loyal Site Supporter
Bruce Clark's Avatar

Join Date: Mar 2010
Location: Ocean Grove, Victoria
Photos: Gallery | Albums
Posts: 4,458
Agree with UncleVanya's points. A longer lens will provide a shallower depth of field for a given aperture and greater control of blur and the objects in the background. Background is very important in macro. A good explanation is in this



.

02-06-2017, 12:32 AM - 1 Like   #5
dms
Site Supporter
Site Supporter




Join Date: Aug 2011
Location: New York, NY
Photos: Gallery
Posts: 2,192
Different perspective for sure--but depth of field is only a function of magnification.
02-06-2017, 01:03 AM   #6
Veteran Member




Join Date: Sep 2013
Location: Sydney
Photos: Albums
Posts: 844
In laymans terms, the 35 is a great everyday lens, that can get very close to subjects. It's a great macro for flowers, and things that don't bite! It's very easy to hand hold and get good images in reasonable light. At maximum magnification, you're subject will only be a cm or so from the front element. Generally though, your hit rate at macro lengths will be 1 in 4 or so.

The 100mm, as with all telephoto lenses, require a higher shutter speed or extremely steady hands to hand hold. On a tripod that's less of a concern obviously. The working distance at maximum magnification is much further away, so taking shots of insects that bite is a less terrifying experience than with the 35mm. The dof is much thinner wide open, so you'll probably doing macros at f8+, so you may find a tripod and/or flash vital extras if you're going for 1:1. Your hit rate for this lens will probably be in the region of 1 in 20.

The 50mm sits somewhere between those two extremes. As a first macro lens, this isn't a bad focal length to consider.

My favourite of the 3 is still the DA35, although that's not FF (the other two are). I find the 100 substantially easier to control on the k-1 than I ever did on the k-3. Great lens for the k-1, frustrating on the k-3 (but does occasionally do something magical!)
02-06-2017, 02:32 AM - 1 Like   #7
Moderator
Not a Number's Avatar

Join Date: Mar 2012
Location: Venice, CA
Posts: 10,503
Basically the shorter the focal length the shorter the minimum focus distance. A 50mm lens may have a MFD of 0.45m while with a 28mm lens the MFD may be around 0.26m.

Adding extension to a lens allows you to focus closer than the "normal" MFD. The closer you can get with extension the more magnification. Basically magnification is the ratio of the extension vs the focal length of the lens. A 50mm lens with 50mm extension gives you 1x. 100mm of extension gives you 2x. The mathematics is a bit more involved but for ball park numbers it is good enough. Wait a minute, what about say the SMC-A 50mm macro? You only need 25mm extension to get 1x. That's because it has 25mm extension built into it - the max magnification without a tube is 0.5x.

The advantage of using a shorter focal length lens is you can get greater magnification with less total extension. A 20mm lens with 100mm extension would give you ~5x magnification. As noted in a few posts above the drawback is the shorter the focal length the shorter is your working distance. Working distance is (however you want to measure it) the distance between your subject to the filter ring, front of the lens or sensor. With short focal length lenses and depending on the magnification the working distance to the front of the lens can be minuscule.

02-06-2017, 04:48 AM   #8
Site Supporter
Site Supporter
Lowell Goudge's Avatar

Join Date: Jan 2007
Location: Toronto
Photos: Gallery | Albums
Posts: 17,828
Just to put some perspective Ito the statement working distance, consider this

A lens achieves 1:1 reproduction ratio when the subject is at twice the focal length. This means for 1:1 with A 35mm macro this means the subject is 70mm away, that's less than 3 inches, where as a 100mm macro has you 200 mm or 8 inches away for the same magnification.

If you are doing close copy work inside, a 35mm, or perhaps even 50mm is ok, but outside , many things, insects especially don't let you get that close.
02-06-2017, 05:05 AM - 1 Like   #9
Veteran Member
Na Horuk's Avatar

Join Date: Feb 2012
Location: Slovenia, probably
Photos: Gallery | Albums
Posts: 11,186
Magnification on macro lenses is usually written as 1:1. This means that the subject projected onto the sensor is the same size as the subject. This only occurs at the minimum focus distance. With 35mm your MFD is much smaller than on 100mm. You have to get much closer to get the same magnification. You can get the same magnification, but things like perspective and subject isolation will be different. This has many implications.
For example, if you want to photograph a skittish or dangerous creature, it will be difficult to get close enough with 35mm. 35mm, because you are closer, would mean you might cast shade onto the subject. Its difficult to get lights between the lens and the subject at that focal length in macro range.
Ultimately, it comes down to longer focal length (like 100mm) is easier to use, especially for beginners. 35mm macro is more for advanced users who know what they want and how to use such extreme lens. However! The DA 35mm macro is a well loved lens. It is quite sharp even in non-macro range, and can be used as a normal 35mm lens. In fact, it seems to be sharper than the DA 35mm f2.4. Macro lenses generally have high corrections, so they are sharper and better than non-macro lenses. But their downsides are slower AF (due to long focus throw), lower aperture, and a more "clinical" look to the photos (not so much character). The two DFA lenses are full frame, while the DA 35mm f2.8 macro is not full frame at all focus distances. So if you plan on using it on K-1, you might want to skip the DA 35mm f2.8. (The non-macro DA f2.4 is better on FF, but it is not macro at all. Still a decent lens, at a really low price)
Now, 100mm generally "brings subjects closer" when you are not in the macro range. But when you come to the range where magnification is written, then that is the magnification. For example, shooting 35mm and 100mm at infinity will be quite different - 35mm will be wide angle, 100mm will be telephoto and bring faraway subjects close. But in macro, magnification is set, so only difference is how far you are from the subject.

tl;dr: 1:1 magnification can be achieved by many focal lengths, but it is easier to handle with longer ones. Buy the DFA 100mm macro. Get the DA 35mm macro later or buy it now if you plan on also using it for non-macro purposes. All modern macro primes have really good optics at a fairly decent price point.

Last edited by Na Horuk; 02-06-2017 at 05:12 AM.
02-06-2017, 06:12 AM - 2 Likes   #10
Veteran Member




Join Date: Jul 2009
Location: Tromsø, Norway
Photos: Albums
Posts: 1,031
Think of portraits taken with 35, 50 and 100mm. Keeping the frame (shoulders + head + a little air over the head) equal. The magnification stays the same, but your working distance and "compression" will be different. Its the same thing for macro work.

Typically short focal length macros are good for flowers and other small non moving things, where you want to see the surroundings in the background. Longer focal length macros are good for living insects because you get longer working distance and don't scare them off that easily. They can be used for flowers and such too, but you will not see the surroundings as much in the background. If its shoot handheld wide angles are easier to hold still because of the 1/focal length rule. I don't think SR are as effective at macro focal lengths as they are with longer focus distances.
02-06-2017, 06:28 AM   #11
Site Supporter
Site Supporter
TER-OR's Avatar

Join Date: Apr 2009
Location: Dundee, IL
Photos: Gallery | Albums
Posts: 6,699
QuoteOriginally posted by 65535 Quote
I see 35mm, 50mm, 100mm macro lenses. What is the difference in the kind of pictures they produce?

Does 100mm mean more magnification?

What kind of macro photography are you interested in?
02-06-2017, 07:32 AM   #12
Seeker of Knowledge
Loyal Site Supporter
aslyfox's Avatar

Join Date: Aug 2016
Location: Topeka, Kansas
Photos: Gallery | Albums
Posts: 24,559
QuoteOriginally posted by TER-OR Quote
What kind of macro photography are you interested in?
another thought from a newbie at macro, if I may, I have two macro lenses with my K 3

the pentax 100 macro (no WR) and

a tamron 70 - 300 mm macro zoom ld 1:2.

I have learned that the best the tamron will do is a 1:2 but only if the lens is maxed out to 300 mm. Obviously the 100 is better at 1:1.

however, if I should be out shooting carrying the 70 - 300 and come across a image I want to attempt macro, I'll take the shot. I am amazed at the results I can get from cropping the image in pp.

not perfect but still nice for not using a true macro especially since I am not using flash or shooting in staged environments

if I have the time or am using the 100 macro, then I am better off for macro except how close I need to get to the subject and how skittish it may be.

BTW I'm a seeker of knowledge so anyone have more hints I would love to hear them.
02-06-2017, 07:38 AM   #13
Site Supporter
Site Supporter
TER-OR's Avatar

Join Date: Apr 2009
Location: Dundee, IL
Photos: Gallery | Albums
Posts: 6,699
Yeah, when I was using a Tamron 70-300 I found it pretty good at that as well.
I may have to dig it out and try some tests. I don't use it now because the purple fringing was so bad, but in the macro situation this may not be such an issue.
02-06-2017, 09:58 AM   #14
Senior Member
flugfiske's Avatar

Join Date: May 2014
Location: Nurmijärvi
Photos: Gallery | Albums
Posts: 140
These are taken with tamron 70-300, works nicely, if there is enough light, so you can use small aperture:

https://www.pentaxforums.com/forums/attachments/12-post-your-photos/316140d1...us-lauhis1.jpg

https://www.pentaxforums.com/forums/attachments/177-macro-photography/319194d1469279617-bumblebee-kimalainen.jpg

If you compare those two pics to this one, which was taken with 10-17mm pentax fish-eye, you see the difference between long and short lens.
For example my Laowa 15mm wide angle macro, gives full 1:1 ratio, if subject is about 12mm from front lens, all af my models do not like that, and often fly or run away...

https://www.pentaxforums.com/forums/attachments/177-macro-photography/319376...en_ohdaake.jpg

This is taken with reversed lens, cheap combination, lens 15€ and adapter 3€. With this, you can get reeaaallly close.

https://www.pentaxforums.com/forums/attachments/177-macro-photography/320882...r-petolude.jpg

And my favourite "macroist" Mr Shahan tells much about macro photography in his youtubechannel and website (link to the channel is there on the website)

Thomas Shahan!
02-06-2017, 10:42 AM   #15
Senior Member
LoneWolf's Avatar

Join Date: Nov 2014
Posts: 141
QuoteOriginally posted by 65535 Quote
I see 35mm, 50mm, 100mm macro lenses. What is the difference in the kind of pictures they produce?

Does 100mm mean more magnification?
An interesting question with interesting replies.

However without knowing whether responder is making his / her comment based on full frame or APS-C (or eqivalent) some of the answers could be misleading. It would be appreciated if responders would state where they are coming from. It is a common omisssion when giving opinions and it is often (too often) a very frustrating one. 35mm, 50mm, 100mm in full frame gives 52.5 mm, 75 mm, 150 mm in APS-C: quite a difference.
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!
100mm, camera, macro, macro lens length, pentax help, photography, question macro lens, troubleshooting
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Lens mechanics question: Aperture vs focal length joseph_me Pentax SLR Lens Discussion 7 10-06-2015 10:46 PM
Macro Quick Macro Focal Length Question... vagabond79 Photographic Technique 7 08-26-2014 04:33 AM
lens hood length question chris* Pentax SLR Lens Discussion 3 03-22-2012 03:41 AM
Basic Lens Question form a New User stonecreek Pentax SLR Lens Discussion 12 04-28-2011 06:20 AM
Stupidly basic question about a lens. Vormulac Pentax SLR Lens Discussion 8 06-27-2009 09:57 PM



All times are GMT -7. The time now is 10:26 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