vignetting etc: what happens if I mount 3 filters on a 35mm lens?

[papasnap]

quick question, not very urgent/important (I'll find out the hard way in a couple of weeks anyway). I shoot a nokton 35mm f1.2, which always has a B+W UV filter on it for protection. As I want the option to shoot at or near wide open in daylight, I've just ordered two hoya ND 8 filters - I'm planning on mounting them one on top of the other (to give a combined 6 stop reduction in light), with the ND's on top of the UV filter for a total of 3 filters at once.

Do you think this will result in any blockage of the frame? Vignetting is fine (in fact I like it a lot), but I wouldn't be so keen on a total blackout of the edges..

cheers,
papasnap

 

[Avotius]

why do you need the UV filter if you are going to have two ND filters on top of it? Loose the UV and you may not have problems, but im not sure what the clearance is like on the nokton.

 

[papasnap]

boy do I feel like a dunce. I didn't even think of that! definately time to go to bed.

thanks avotius! am still keen to try the triple filter though - a bit of vignetting can be a nice look.

cheers,
papapsnap

 

[Avotius]

As true as that is, and I do add vignetting to my photos that I think could use it for effect, its so much easier to do in photoshop then on the film. Also filters will give you "hard" vignetting, but in photoshop using the circle selection tool with a feather of whatever you wish (12megapixle files I use a feather of 250) then select one side to the other creating a nice oval, inverse selection, then fill it in black in a new layer, the monkey with the opacity as needed.

 

[uhligfd]

Why not experiment and tell us what happens with 4 or 5 filters on the lens?

Photography is so much fun, since at the moment of exposure we generally do not know what will come out. Ever left your lens cap on? Perfect vignetting in my book. Cheers!

 

[laptoprob]

Light travelling diagonally through a filter will lead to more vignetting in the corners than in the middle, creating a gradual hotspot. This happens especially with ultrawides. I noticed it with a polafilter on my 15mm Heliar.
I think it will also happen with your 35mm.

 

[Luddite Frank]

I'm curious - why are you looking for such a drastic reduction in light, to shoot wide-open: are you planning to under-expose / overdevelop, or could you just use a slower film, open-up the lens, and eliminate the ND filters altogether ?

( Not trying to be critical - it is a genuine "innocent question" 🙂 )

Luddite Frank

 

[hans voralberg]

May be it's sunny where he lives, when I was in SE Asia, and shooting the Noctilux in daylight, even with Velvia 50 I need 2 stop ND as not to over expose every frame

 

[Luddite Frank]

May be it's sunny where he lives, when I was in SE Asia, and shooting the Noctilux in daylight, even with Velvia 50 I need 2 stop ND as not to over expose every frame

That's an environamental consideration that would never have occured to me, here in Northeastern Pennsylvania, USA - from September to mid-May, the skies are generally leaden-overcast. 🙁
Truly bright, sunny days are somewhat rare here.


I thought about checking-out the multiple-filter stack / vignetting issue with one of my SLRs, but the fastest wide-angle I have is the 2.8/35 Flektagon for my Exakta, and I don't have any filters for that...

Regards,

LF

 

[Jonathan R]

Adding all those glass-air surfaces will add considerably to any flare problems. But if you use a lenshood too, your vignetting problems will get worse.

Would a gel holder with a couple of gel ND filters be a thinner option?

 

[pevelg]

Why use 2 ND filters anyway? Get a ND 1.8, which decreases the light by 6 stops.

I'm curious - why are you looking for such a drastic reduction in light, to shoot wide-open: are you planning to under-expose / overdevelop, or could you just use a slower film, open-up the lens, and eliminate the ND filters altogether ?

I use ISO 100 almost all the time and am starting to use ISO 64. There are MANY situations where I wish I could have less light. The real reason is shutter speed and DOF. Last summer on my trip to AK, I wanted to shoot some creeks in the mountains. Closing my lens to F22, I was shooting at around 1/125. I wanted to have the water be slightly blurred, but couldn't due to the fast shutter speed. A ND filter would have done wonders. Similarly, if I wanted to use a shallow DOF, I would set my camera to fastest shutter speed, 1/1000, and I'd still have the F stop be at around f8. And this is all at ISO 100.

EDIT:
Here is a list of ND light reduction from B&H



Neutral Density factors
•

ND.3 (exposure adjustment = 1 stop, reduces ISO 1/2)


•

ND.6 (exposure adjustment = 2 stops, reduces ISO 1/4)


•

ND.9 (exposure adjustment = 3 stops, reduces ISO 1/8)


•

ND 1.8 (exposure adjustment = approx. 6 stops, transmits 1% of light,)


•

ND 3.0 (exposure adjustment = 10 stops, transmits 0.1% of light)


•

ND 4.0 (exposure adjustment = 13-2/3 stops, transmits 0.01% of light)


•

ND 6.0 = (exposure adjustment = approx. 20 stops)

 

[Avotius]

excuse my lack of knowledge on suchs things, but where would you use a 20 stop ND filter? Astro photography? Studio?

 

[pevelg]

I've seen ND filters to eliminate people. With a 20 stop ND filter, you'd have to have a very long exposure. As people are walking past the camera, it is not recorded in detail. The images are certainly not perfect and you know there is something amiss, but it is a very neat effect. I myself do not using anything stronger than a 0.9 (3 stops)

 

[papasnap]

Avotius - thanks for the good advice, I'm still struggling with a mild allergy to postprocessing but I'll probably get over it in time. As long as it's in moderation, I guess PP is ok. Although I must say I love how physical and tangible shooting slide film is - it's unforgiving, but when you get it right, it's perfect, a little universe in 24x36mm. I was never very happy when shooting digital, shots generally had lifeless quality unless photoshopped. One day I looked again at some medium format provia my dad had shot and was instantly hooked.

I've seen ND filters to eliminate people.

I laughed when I read that, although it does make good sense.

Luddite Frank, hans & pevelg have got it. In a couple of weeks I'm off to south east asia for a few months, and am expecting plenty of bright light. I shoot 95% of the time at iso 1600 (provia 400x +2 stops) as I shoot mostly at night, so rather than worry about constantly loading and unloading half-used rolls, I'd rather just slap an ND on in the day and take it off at night.

Pevelg, good point - that's probably what I should have done. I took a quick scan through ebay for 52mm filters and the darkest I saw were ND8's (3 stop reduction) - so I just went ahead and bought a couple of them, as they were pretty cheap.

Thanks again all!

 

[hans voralberg]

Where about in SEA are you going papasnap? Cause I'll be there for quite a while as well, starting June. I'll be shuffling back and forth between Vietnam and Cambodia, may be sometimes in Singapore as well.

 

[papasnap]

Where about in SEA are you going papasnap? Cause I'll be there for quite a while as well, starting June. I'll be shuffling back and forth between Vietnam and Cambodia, may be sometimes in Singapore as well.

hey hans, I'll be spending time in thailand mainly, but am planning on visiting vietnam, laos and cambodia while I'm at it. I'll be there from start of may to probably end of august - will get in touch again around june, if we're in the same country at the same time we should go for a beer!

cheers,
papasnap

 

[hans voralberg]

Sure thing, and bring lots of film, they're not exactly easy to find anywhere except Spore.

 

[papasnap]

thanks hans! BTW, I started a seperate thread about my trip here (link) - cheers! papasnap