I.R. filters and digi cams

[Fidley]

I saw a picture with really punchy shadows (think it was on here, might hvae been hoodmiester). The effect of it was amazing imo, and i want to achieve the same thing. Just wondering (as i only use a digital camera) it would actually work on me cam before i shell out 20 quids?. TIA

PS: The pic was of an old railway carriage, complete with fencing (great pic) if anyone wants to own up.

[hoodmeister]

/waves hands in the air

That would be me ¬_¬

What digicam do you use? Some are more sensitive than others to IR light...

[Fidley]

Nikon d50. Meant to say in your thread, nice pic!

[BroadbandPlacey]

oh yeah, nikons are great IR cams (apparently - i dont own one so i cant comment much)

[hoodmeister]

All of the Nikon digital SLR lineup (save for the D200) are great IR cameras, yes - so you're all set

I use a Nikon D70 btw.

[Fidley]

Ace. Thanks guys. Is a cheapy one from jessops gonna be ok? I saw that the cookin ones have rating as to the mininum focal length you should use them with (marketing BS?). Me smallest lens goes down to 18mm, that 1.5x iirc effective tho (dunno if that makes any odds to the filter)? BUT they are mega spendy and i ain't all that rich atm.

[hoodmeister]

should do the job, better to start with a not-so-expensive filter and get a feel for it, then get different // more at a later date if you use it a lot.

The Cokin isn't really BS - the filter holders will cause nasty vignetting at wider lenghts - should be OK with the kit lens, not to mention rotating it usually helps (but stops you using ND grads properly).

I'm building up quite a collection of IR filters now. I have all sorts
Got a nice big set of Kodak gels coming my way from the US in a couple of weeks too, looking forward to playing with them

[Fidley]

Cool, ya rich bugga. Wish i had money to burn on filters atm...... i'm gettin married aggghhhhhhhhrrrrrrrrrrr

[Fidley]

Ok where to buy one from then? Been to jessops they swear they don't do a 52mm (lookin for screw in really), i could have sworn that it was on their webby last night but they're adamant., so get home search their webby and find a 52mm hoya jobbie, but it's a 2-4 week wait anyway. So any ideas guys?

PS: I prefer the idea of a screw in filter, but whats the actual benifits of screw and slot (or whatever it's called). Thanks.

[hoodmeister]

/hangover

The pros and cons of different filter types are tough to weigh up.

The obvious answer is always a screw in filter, but the problem there is that, lets say you get a 52mm today for your kit lens, you may only need to buy another in a years time when you get... "x" lens which has a 62mm filter thread.

So sometimes a more "all round" solution is somethning like a Cokin filter holder. The way that works is that you get a holder with different adapter rings, and slot a "pane" filter into the holder, with the right ring on for your lens. That's a bit more pricey though, also takes longer to setup - and the basic Cokin system is only any good for up to 62mm threads.

WarehouseExpress sell a 52mm Hoya R72 for £23.90, excluding delivery. Other places may be cheaper.

The third option is rear filters. These are usually very thin (like paper) polyester or gelatin filters that sit in a small holder behind the lens.
These aren't so great for all sorts of reasons -
you're messing around near the flange & CPU contacts, lots of things to damage if you're not careful.
Just taking the lens off and naffing around with it has the obvious risk of lens droppage.
On a dSLR you're also doing a ton more "lens changes" than you need to = more chance of dust getting in.
They do have the advantage of being an awful lot cheaper than front filters if the filter thread is large though - ie on my Sigma 15-30mm a rear filter is far more economical than an 82mm screw in // Cokin filter.

However, I almost always use rear filters. Both screw in filters and drop in Cokin ones increase the chance of flare - no biggie for "normal" filters, but you get weird flare with IR - tbh I don't really understand it, but you can't see it before you shoot, and you often get it when you least expect it - on an overcast day etc..
I just get far more "keepers" with rear filters.

Having said all that, I think the best place to start is a screw in filter. It's OTT to invest in a Cokin filter system at the moment, and the 18-55 doesn't have a rear filter holder...

[Fidley]

Ok cheers for the advice.

I've looked at the cokin system and tbh it ain't all that expensive, 7ish squid for the holder, 7ish squid for the adaptor + i have a 62mm dia lens (70-300mm), it would be nice to have filters for it. Theres one other thing, it's my birthday today (24 btw ) and the misses hasn't bought a pressie for me yet I think it would make a nice one, to keep for years and i'll get good use out of it, even if i don't end up using the I.R. one too much others will be bought later on. The price of the filter itself seems to be about the same as a screw in AND it'll work on both lenses.

One other thing, can you stack filters with the cokin system, i.e. use more than one at a time?