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02-11-2010, 05:54 AM   #1
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Lens greater than F32

Hello,

I'm looking for a lens that will let me go the above f32, so I can attempt to get some lightning strikes in the daytime. Anyone have any suggestions? My 70-300mm tammy can almost go that high, but I'd prefer something shorter.

I ask because my technique/theory is to set focus to infinity, 400 (lowest possible) iso, highest F value, then bulb it up with the remote. It just lets too much light in though.

I had some success with this technique at night time, the only change being the reverse in F value - I used lowest possible, 4.6 I think.

PS. I'm very much a newbie, so please go easy on the lingo.

02-11-2010, 07:37 PM   #2
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If you just want this to let in less light and aren't specifically trying to create special effects from the severe diffraction artifacts you'd likely see at extremely small apertures, why not just get a neutral density filter to use with a "regular" lens? OK, some lingo there, but Google should help (diffraction, neutral density filter).
02-11-2010, 07:55 PM   #3
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Definitely look at one of the filters that Marc mentioned. When you get much above f8, you start getting diffraction. Even with a good lens, it will be fairly severe by the time you get to f32. Much better just to put a filter over the end of your lens that lets in less light. These are also useful if you want to get flowing water fall photos during the day.
02-11-2010, 08:49 PM   #4
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That sounds cheaper than a new lens! Helpful and saves me money.. I like it! Thanks very much for the tips. Is there a +rep feature here somewehre?

You mention the flowing waterfall - not something I've tried to shoot before, but it sounds like an interesting subject. What issues arise with them?

02-11-2010, 09:00 PM   #5
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QuoteOriginally posted by schitzengiggles Quote
That sounds cheaper than a new lens! Helpful and saves me money.. I like it! Thanks very much for the tips. Is there a +rep feature here somewehre?

You mention the flowing waterfall - not something I've tried to shoot before, but it sounds like an interesting subject. What issues arise with them?
To get the "cotton candy" effect in the water, you need a longer shutter speed, which would end up over exposing in the daylight.
02-11-2010, 11:18 PM   #6
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QuoteOriginally posted by schitzengiggles Quote

You mention the flowing waterfall - not something I've tried to shoot before, but it sounds like an interesting subject. What issues arise with them?
Although this was done with Low ISO (50) and a high F-stop.... No ND filter it's the effect that you can sometimes have while doing long exposures with moving water.

It's a 2.5 second exposure.
The thing with moving water is some people like it frozen, while others prefer a creamy white look. Others prefer something in between. So you'll never please everyone with just one photo.
02-11-2010, 11:39 PM   #7
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QuoteOriginally posted by little laker Quote
Although this was done with Low ISO (50) and a high F-stop.... No ND filter it's the effect that you can sometimes have while doing long exposures with moving water.

It's a 2.5 second exposure.
The thing with moving water is some people like it frozen, while others prefer a creamy white look. Others prefer something in between. So you'll never please everyone with just one photo.
At ISO 50, I somehow doubt you did that with a Digital SLR. People keep whining about High ISO. I'd love to have ISO 50 or even 25. I guess that's partially why my cameras tend to stay pegged at ISO 100.
02-11-2010, 11:44 PM   #8
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cheap New Cap Pinhole Lens Red - 35mm DSLR/SLR Pentax Camera - eBay (item 400033877074 end time Feb-21-10 19:38:54 PST)

F 168 But if you want sharp pictures go with the ND filter

02-12-2010, 12:22 AM   #9
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QuoteOriginally posted by JeffJS Quote
At ISO 50, I somehow doubt you did that with a Digital SLR. People keep whining about High ISO. I'd love to have ISO 50 or even 25. I guess that's partially why my cameras tend to stay pegged at ISO 100.
I didn't say that it was done with my Pentax, Jeff. It's done on digital, check the data, it's all there. I'd love to have ISO 25 as well, but it may take a while for Digital to reach it. It seems that most people want High ISO, which I could live without.
02-12-2010, 12:30 AM   #10
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Another vote here for the ND filter that Marc told you about. That is exactly what they are made for (to reduce the amount of light coming in to your lens. so you can use longer exposures.)

From what I understand you want to significantly reduce the light coming in your lens, so you can use very long exposures and increase the likelihood of capturing lightning? That is a very interesting idea. I hadn't thought of doing that before, but it makes sense. It should result in some very interesting pictures!

My guess is that he would have to use a pretty "heavy" ND filter, right? I personally do not own one.


With regards to the "creamy vs sharp" water debate; I like my water sharp. I want to see every molecule of water completely frozen in space and time. I like it so sharp that it looks like you can see every drop, and the water could cut you. But that is just me.
02-12-2010, 12:42 AM   #11
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Has anyone tried photographing lightning with a Pinhole lens
I'm thinking that it'd be a pretty long exposure, plus it may be an interesting effect.
02-12-2010, 12:48 AM   #12
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google found this Flickr: Pinhole lightning
02-12-2010, 03:06 AM   #13
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rikki pool who is a renowned weather photographer in australia taught me the low f value, low iso, 30sec - if not bulb exposure method for night time strikes.

i imagine that the reverse would almost apply. though nobody has yet confirmed my theory. too many people hide the properties of their images on flickr, so i'll go buy one of these filters and wait for a storm and report back

again, thankyou for the tips.

Last edited by schitzengiggles; 02-12-2010 at 03:12 AM.
02-12-2010, 03:09 PM   #14
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QuoteOriginally posted by schitzengiggles Quote
I'm looking for a lens that will let me go the above f32.
S 24-135/2.8-4.5 goes down to f51 @ 135mm
02-12-2010, 08:22 PM   #15
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I am a lightning guy and have been involved in a number of research projects where we have had to photograph it in daylight.

You have basically two options. The simplest (and the one I've used quite a lot) is an infrared filter. Lightning has strong light emissions at various wavelengths. A really useful wavelength is Hydrogen-alpha (about 6563 angstroms). Professionally, I used a narrow-band H-alpha filter to obtain time exposures of five minutes or more in daylight. As an amateur, I've used less-expensive infrared filters that cover this wavelength.

The second option is a light trigger. Lightning is quite a long-duration event and can involve a number of successive discharges. A sensitive light trigger that fires the camera when a light pulse is sensed can work quite well in daylight.

Google away!

Mike
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