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Esco1782
09-18-2009, 09:29 AM
When I'm using MF with the kit lens, I love the fact that the manual assistant blows up the image in the LCD 5x so I can see what is in focus. However, I recently bought an adapter and tried out my Canon FD 1.4 lens. It has really nice shallow DOF but I had the hardest time getting my subject in focus. It looked focused on the LCD but then on playback on my computer, it was definitely not. Any tips in correcting this? I feel like knowing whether something is in focus for me is just a big guess as I can't really tell from looking at the LCD.

Martti Ekstrand
09-18-2009, 10:00 AM
Click the left button on the key pad. A yellow frame appears. Click OK mid button. The yellow frame zooms in 5x. Turn the front scroll wheel one click. Zoom is 10x. Turn again. Zoom is 5x. Find focus. Click scroll wheel, OK button or start recording. View is back to full frame. All described in the manual btw.

Ken Steadman
09-18-2009, 10:01 AM
Doesn't your lens have the focus distances on it? Tape measure it out.

holdingpattern
09-18-2009, 10:15 AM
I am not an expert at manual focus, nor have I used that lens, but in playing with manual focus on the kit lens (all I have right now) I have found what seems to be a useful indicator of focus in some situations, without having to resort the the mechanism that Martii describes.

First try manual focus taking pictures before going to video. If there are any fine patterns in the picture with reasonable contrast you will probably start to see some aliasing (jaggies, shimmering or sparkling of the pattern) on the LCD. This usually means the part of the photo where you see the aliasing is in or near focus.

This isn't a failproof means to get focus because many scenes do not have patterns that work for this, but I found it usefull to get a feel of how the manual focus responds and what the image on the LCD looks like when the image is in focus.

Good luck.

Esco1782
09-18-2009, 11:08 AM
Thanks for the help guys. I'm reading the manual on the subway to and from work, I can't believe I missed that info.. Anyways, this is a great forum. thanks again.

holdingpattern
09-18-2009, 11:15 AM
Doesn't your lens have the focus distances on it? Tape measure it out.

If it does, the distances are probably for a full frame 35mm camera. How does the crop factor of the GH1 affect these distances? Multiply by 2? divide by 2 or are the numbers basically useless for a GH1?

Thanks.

P.S. I also have found this forum incredibly usefull and have learned a lot not just about the GH1 but filmmaking in general. Now I just have to figure out how to put all this information to good use ...

offstandard
09-18-2009, 11:40 AM
focus distance is the same no matter what the crop factor, you're just not getting the full framing, but the distance to sensor to focus point would not have changed. Otherwise you'd have trouble with infinity focus and other issues. =)

holdingpattern
09-18-2009, 11:50 AM
focus distance is the same no matter what the crop factor, you're just not getting the full framing, but the distance to sensor to focus point would not have changed. Otherwise you'd have trouble with infinity focus and other issues. =)

That makes sense... I think... that sounds like why it is important that the adapters you get for these lenses are as big as they are, to put the lens at the right position (simulate the flange distance of an SLR) for focus, and probably other things too...

Thanks.

BhambuNath
09-18-2009, 08:10 PM
One thing I've found out is that you should always double check the focus through view finder which gives a lot better view of what is in sharp focus than just looking at the LCD.