Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
05-12-2016, 08:19 AM   #1
Site Supporter




Join Date: May 2015
Location: Hampshire
Photos: Albums
Posts: 252
Shake reduction setting for macro lens.

I have just acquired a Sigma 50mm Macro F2.8 (with A contacts) and am wondering if I should use the 50mm setting for the shake reduction or set for a longer lens.


My reason for querying this is the length of the lens in macro. I have recently bought a 135mm lens that is not as long fully extended. I intend to use this lens stopped down a fair bit to get the DOF as large as I can without upping the ISO too much and am likely to use it hand held (with pretty shaky hands) so would appreciate best SR I can get.
.
I am assuming the length of the lens determines the amount of SR provided by the camera. I'm probably wrong.


If this has been covered in other posts I apologise.

05-12-2016, 08:30 AM   #2
Pentaxian
Rimfiredude's Avatar

Join Date: Oct 2014
Location: Washington
Photos: Gallery
Posts: 2,174
use the 50mm setting
05-12-2016, 08:55 AM   #3
Pentaxian
Not a Number's Avatar

Join Date: Mar 2012
Location: Venice, CA
Posts: 3,897
Yes set it to 50mm. I think shake reduction gets less effective the closer you get to the subject (more magnification), but that's my opinion/feeling. Make some tests and judge for yourself.
05-12-2016, 09:15 AM   #4
Moderator
Loyal Site Supporter
BigMackCam's Avatar

Join Date: Mar 2010
Location: North East of England
Posts: 5,542
As already mentioned above, you should set it to 50mm. It's the focal length that is important to the SR, rather than the physical length of the lens.

05-12-2016, 09:46 AM   #5
dms
Site Supporter




Join Date: Aug 2011
Location: New York, NY
Photos: Gallery
Posts: 1,550
Although it is not a change in focal length (as FL is normally defined), nevertheless close up focusing generally involves adding extension to the lens.
Thus seems like the SR setting should change. If it is m=0.5, one is adding 50% extension, thus 50 mm is 75 mm. (One of the things I was meaning to do more with--on paper and by trial--but didn't.)
05-12-2016, 10:25 AM   #6
Loyal Site Supporter
UncleVanya's Avatar

Join Date: Jul 2014
Photos: Gallery | Albums
Posts: 9,509
Given the fact that focal length normally is indicative of the sensitivity to the movement of the lens. I think making some test shots may be best - the amount of movement of the image circle is what is really important.
05-12-2016, 10:40 AM   #7
Moderator
Loyal Site Supporter
BigMackCam's Avatar

Join Date: Mar 2010
Location: North East of England
Posts: 5,542
QuoteOriginally posted by dms Quote
Although it is not a change in focal length (as FL is normally defined), nevertheless close up focusing generally involves adding extension to the lens.
Thus seems like the SR setting should change. If it is m=0.5, one is adding 50% extension, thus 50 mm is 75 mm. (One of the things I was meaning to do more with--on paper and by trial--but didn't.)
QuoteOriginally posted by UncleVanya Quote
Given the fact that focal length normally is indicative of the sensitivity to the movement of the lens. I think making some test shots may be best - the amount of movement of the image circle is what is really important.
If we should be using a value greater than the focal length for close-up / macro work, I wonder how that affects something like the DFA100 where the camera automatically picks up the 100mm focal length from the lens firmware? Unless, of course, the camera also looks at focus distance and adjusts SR based on that information too...
05-12-2016, 10:50 AM   #8
Loyal Site Supporter
UncleVanya's Avatar

Join Date: Jul 2014
Photos: Gallery | Albums
Posts: 9,509
QuoteOriginally posted by BigMackCam Quote
If we should be using a value greater than the focal length for close-up / macro work, I wonder how that affects something like the DFA100 where the camera automatically picks up the 100mm focal length from the lens firmware? Unless, of course, the camera also looks at focus distance and adjusts SR based on that information too...
I don't know if we should but it seems possible. Adding a Raynox to any lens would have this same impact.

05-12-2016, 10:56 AM   #9
Pentaxian
Na Horuk's Avatar

Join Date: Feb 2012
Location: Slovenia, probably
Photos: Gallery | Albums
Posts: 10,325
I think SR should always be the same value as written on the lens, or closest wider value if the exact same number is unavailable (for example, on my K-01 I can't input 58mm, so I input 55 instead; not 60). This way, SR will undercompensate instead of overcompensate. It is better to get less effective SR than to get SR-added blur.

Yes, at macro range the SR might not be optimally effective, because the magnification is so high. I never actually thought about inputting a higher SR focal length value to improve SR in macro range. Its an interesting idea, you can try experimenting, but I think its futile.
For most macro work you will hopefully be using some sort of tripod or other stabilizer, with flashes or lights. If you have that, then SR won't be needed anyway.
I have a DFA 100mm macro and don't really have much faith in SR in the macro range (1:2 - 1:1). Its just such a high magnitude of shake.. think about it. In macro, sometimes the DoF is just a couple millimeters, or even less. This means if your hands shake by 1mm, it can cause major problems. And 1mm of handshake is not outrageous.

Macro photo is all about technique and set up!
Good luck

Last edited by Na Horuk; 05-12-2016 at 01:00 PM.
05-12-2016, 10:59 AM   #10
Moderator PEG Judges
Kerrowdown's Avatar

Join Date: Aug 2008
Location: Highlands of Scotland.
Photos: Gallery
Posts: 30,638
+1, IMHO set to 50mm, well that's certainly what I do with my “Femme Fatale” (SMC Pentax-A 50mm F2.8 Macro).
05-12-2016, 10:59 AM - 1 Like   #11
dms
Site Supporter




Join Date: Aug 2011
Location: New York, NY
Photos: Gallery
Posts: 1,550
QuoteOriginally posted by BigMackCam Quote
If we should be using a value greater than the focal length for close-up / macro work, I wonder how that affects something like the DFA100 where the camera automatically picks up the 100mm focal length from the lens firmware? Unless, of course, the camera also looks at focus distance and adjusts SR based on that information too...
My understanding is only the focal length is (auto.) used for FA and later lenses. This may be why the camera manual cautions [from K-5 manual] "The effect of Shake Reduction is influenced by the shooting distance as well as focal length information. The Shake Reduction function may not work as effectively as expected when shooting at close ranges."
05-12-2016, 11:05 AM   #12
Loyal Site Supporter
UncleVanya's Avatar

Join Date: Jul 2014
Photos: Gallery | Albums
Posts: 9,509
Since focus breathing and even macro add on lenses can be expressed in focal length changes can't we calculate the theoretical focal length needed? Isn't 1mm within the range that the SR can handle? I'm not asking about tripod shots here - just the handheld ones. I have shot macro both ways and while I don't think a 1:1 shot is all that likely to be hand held by me - there are people who do it (with flash - bright outdoor sunlight etc.)

Isn't there an effective aperture calculation for the use of extension tubes? Doesn't that occur because the effective focal length changes but the lens aperture remains fixed?

Just saying that maybe some math will help narrow the choices a bit and let us experiment.
05-12-2016, 11:21 AM   #13
dms
Site Supporter




Join Date: Aug 2011
Location: New York, NY
Photos: Gallery
Posts: 1,550
Uncle Vanya, that is why I said "not as focal length is normally defined," as it is the ratio of length to opening diameter at (I believe) infinity focus. But yes we are adding to the length as we focus closer and not changing the opening diameter--thus SR likely depends on focus distance (i.e., magification) as well.

Focus breathing is also a reduction in FL as we focus closer (but that is confusing as focal length is I believe said to only apply to infinity--maybe we should have a term "effective" focal length)--so it is likey a more complicated combination of the two.
05-12-2016, 11:41 AM   #14
Site Supporter




Join Date: Dec 2015
Location: Goldsboro North Carolina
Photos: Gallery | Albums
Posts: 295
I've been shooting a lot of macro shots hand-held lately with mixed results; some wonderful, some completely blurred. I use extension tubes and screw on close-up lenses with SR set to the focal length on the lens. I try to keep the ISO and shutter speed cranked up high, and hold my breath before firing. Now I'm wondering if I should turn SR off for some test shots. I could get consistently better results with tripod and ring flash, but that takes setup. I don't carry them everywhere I go. I want to be able to take the best advantage of 'found' opportunities on the spur of the moment.

BTW, when I reverse mount my 50mm lens, does that make the effective focal length 1/50mm? 8)
05-12-2016, 12:25 PM   #15
Site Supporter




Join Date: May 2015
Location: Hampshire
Photos: Albums
Posts: 252
Original Poster
Thank you to all of you who have posted replies to my enquiry. My searching of previous posts regarding shake reduction all seem to indicate that the closer one is focussing, the less effective SR will be.


I have decided to do as Uncle Vanya suggested and experiment, though it's getting dark here I tried the lens with shake reduction off, 50mm FL inputted, shake reduction on, 50mm FL inputted and 100mm FL inputted with SR on.


Just one of each as it is getting darker here so not a valid test at all. All using F4 at 1/20th sec. The result of this quick test.....100mm FL inputted with SR on was the least affected by shake. Shake reduction off provided the worst image.


Hopefully I will get time tomorrow or over the weekend to investigate this further....or start looking for a ring flash to use with macro on subjects likely to move while I am trying to focus and consider humping a tripod around for those static photo opportunities.
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!
50mm, camera, length, lens, macro, pentax help, photography, reduction, shake, shake reduction, sr, troubleshooting
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
K10D - Setting Shake Reduction Focal Length With Manual Focus Lenses? stewart_photo Photographic Technique 30 07-28-2016 12:52 AM
Setting for Shake Reduction? Snoops27 Pentax K-5 8 08-26-2014 04:59 AM
Shake reduction setting for reverse lens stacking macro mythguy9 Photographic Technique 11 01-25-2014 06:44 AM
Shake reduction setting for macro Nick Siebers Photographic Technique 30 03-09-2009 08:15 AM
K10D shake reduction manual setting zoom lens chris hall Pentax DSLR Discussion 7 02-14-2008 08:38 AM



All times are GMT -7. The time now is 01:50 PM. | See also: NikonForums.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