DIY Adapter ghosting problem. Help.

Martin Lindstedt · July 23rd, 2007, 08:50 AM

Ahh, yea, that's right ! Of course, the whole filmstrip is 35mm, but the actual image area is 24x18mm.

Just out of curiosity, ( I don't mean too hijack this thread ) but is there anyway to calculate what my 50mm lens would turn into, if I use the 24x18 area on my groundglass?

Bob Hart · July 23rd, 2007, 05:11 PM

In terms of depth-of-field, nothing changes, 50mm is 50mm, is and always will be, but perspectively, field-of-view becomes narrower so for a similar field-of-view, the 35mm now becomes the "normal" (ballpark only) lens. A 28mm is also near enough.

You don't get the incremental sizes in stills lenses like you can with motion picture lenses. On these wider lenses, f1.4 is ideal, f1.8 adequate but any narrower and you may be more likely to run into a corner falloff (hotspot) problem.

Ben Lau · October 3rd, 2007, 01:42 AM

Hi Lau Ho Ming,

I live in HK as well and I am eager to start building my first DIY 35mm adapter. Seems like you are pretty experienced in this area. It would be greatful if you can give me some advice? Even pointing the direction to where I can find the parts in HK would be helpful~ Please contact me via msn: firebird0415@hotmail.com if you have the time to give me a helping hand. Thank you very much!

Lau Ho Ming · October 5th, 2007, 12:32 PM

I can't believe it XD I thought I'm the only Hong Kong dude. I added your MSN.

July 23rd, 2007, 08:50 AM	#16
Martin Lindstedt Regular Crew Join Date: Jul 2004 Location: Malmö, Sweden Posts: 25	Ahh, yea, that's right ! Of course, the whole filmstrip is 35mm, but the actual image area is 24x18mm. Just out of curiosity, ( I don't mean too hijack this thread ) but is there anyway to calculate what my 50mm lens would turn into, if I use the 24x18 area on my groundglass?

July 23rd, 2007, 05:11 PM	#17
Bob Hart Inner Circle Join Date: Dec 2003 Location: PERTH. W.A. AUSTRALIA. Posts: 4,477	In terms of depth-of-field, nothing changes, 50mm is 50mm, is and always will be, but perspectively, field-of-view becomes narrower so for a similar field-of-view, the 35mm now becomes the "normal" (ballpark only) lens. A 28mm is also near enough. You don't get the incremental sizes in stills lenses like you can with motion picture lenses. On these wider lenses, f1.4 is ideal, f1.8 adequate but any narrower and you may be more likely to run into a corner falloff (hotspot) problem.

October 3rd, 2007, 01:42 AM	#18
Ben Lau Tourist Join Date: Sep 2007 Location: Hong Kong Posts: 1	Hi Lau Ho Ming, I live in HK as well and I am eager to start building my first DIY 35mm adapter. Seems like you are pretty experienced in this area. It would be greatful if you can give me some advice? Even pointing the direction to where I can find the parts in HK would be helpful~ Please contact me via msn: firebird0415@hotmail.com if you have the time to give me a helping hand. Thank you very much!

October 5th, 2007, 12:32 PM	#19
Lau Ho Ming Regular Crew Join Date: Nov 2006 Location: Hong Kong Posts: 81	I can't believe it XD I thought I'm the only Hong Kong dude. I added your MSN.