Go Back   Steve's Digicams Forums > Digital SLR and Interchangeable Lens Cameras > Pentax / Samsung dSLR, K Mount Mirrorless

Reply
 
Thread Tools Search this Thread
Old Nov 9, 2007, 1:20 AM   #41
Senior Member
 
bigdawg's Avatar
 
Join Date: Feb 2005
Location: Thach Alabama
Posts: 14,981
Default

No. 3
Attached Images
 
bigdawg is offline   Reply With Quote
Old Nov 9, 2007, 2:23 AM   #42
Senior Member
 
bigdawg's Avatar
 
Join Date: Feb 2005
Location: Thach Alabama
Posts: 14,981
Default

This is made for a 3" X 4" lens but by putting it in the vise and bending the narrow end outward a little you can use a 3"X 6" lens.Or if you'd rather you can go as big as a 6"X 6" lens as well. The heighth doesn't matter as it just needs the stick-on velcro to attach it and you would have to provide a Rubber band(Old Innertube rubber will do) or get an elastic or velcro strap to attach it. These still need a rubber pad at the narrow end to help keep it in place but some peel and stick rubber or foam pads will work for that. I'll do a little more to it and show the results here. These are very rigid as is but you could glue a 1" wide strip of lexan to help stiffen it even more. I don't right now see why but you could if you wished to.

Dawg
bigdawg is offline   Reply With Quote
Old Nov 9, 2007, 6:48 AM   #43
Senior Member
 
Join Date: Aug 2006
Location: Essex, UK
Posts: 1,868
Default

One thing did spring to mind with all of this.



Why only 2 sides?



Surely if you made it with 4 sides, and just pushed it over the flash head, then all of the flash power would go to the magnifyer at the end.



Or am I missing something obvious here?



Dal
Dal1970 is offline   Reply With Quote
Old Nov 9, 2007, 8:50 AM   #44
Senior Member
 
bigdawg's Avatar
 
Join Date: Feb 2005
Location: Thach Alabama
Posts: 14,981
Default

Dal1970 wrote:
Quote:
One thing did spring to mind with all of this.



Why only 2 sides?



Surely if you made it with 4 sides, and just pushed it over the flash head, then all of the flash power would go to the magnifyer at the end.



Or am I missing something obvious here?



Dal
The Idea is to make it where it will take down into flat pieces and be carrieable in your pocket. Yes more light would be carried to the lens but the difference is negligible. With this lens set up it should give you from 1-2 stops more light at around 20 feet or so. At least that is what the sights I've looked at are saying. I am making some in the near future that are a lot more complicated (with 4 sides and adjustability to aid in getting the light better focused) but that is going to take quite a while and the results (is it better? ) are problematical! Like I said this is just the first of many as I go through the design stage. If this works as good as the four sided one then it will be much, much less trouble to make for a lot of folks out there.

Dawg
bigdawg is offline   Reply With Quote
Old Nov 9, 2007, 1:28 PM   #45
Senior Member
 
bluwing's Avatar
 
Join Date: Jan 2005
Posts: 592
Default

Hi Roy,

You know that Pentax made a flash extender for the 280 and also an attachment for wide angle shots.

I have seen them on eBay a couple of times.

Rudy
bluwing is offline   Reply With Quote
Old Nov 11, 2007, 8:28 PM   #46
Senior Member
 
bigdawg's Avatar
 
Join Date: Feb 2005
Location: Thach Alabama
Posts: 14,981
Default

Some have mentioned they have thin sheets for the lens element so I have tried to accomodate that type of fresnel lens by doing the following. This will hold a 6X4 lens and allow it to slide in and out. It is made from 3 pieces of 1/8" lexan cut out with a band saw and a jig saw turned upside down. I then glued the sections together with hot glue. Watch your fingers while doing the sawing and don't burn yourself with the hot glue.

Update!!!!!! I've found some acrylic sheet that is lighter and a little more flexible so this will weigh next to nothing when done...Still 1/8" thick though but I know even thinner and lighter material is out there if I can find it locally!!

Dawg

No. 1

Attached Images
 
bigdawg is offline   Reply With Quote
Old Nov 11, 2007, 8:28 PM   #47
Senior Member
 
bigdawg's Avatar
 
Join Date: Feb 2005
Location: Thach Alabama
Posts: 14,981
Default

No. 2
Attached Images
 
bigdawg is offline   Reply With Quote
Old Nov 11, 2007, 8:29 PM   #48
Senior Member
 
bigdawg's Avatar
 
Join Date: Feb 2005
Location: Thach Alabama
Posts: 14,981
Default

No. 3
Attached Images
 
bigdawg is offline   Reply With Quote
Old Nov 11, 2007, 8:29 PM   #49
Senior Member
 
bigdawg's Avatar
 
Join Date: Feb 2005
Location: Thach Alabama
Posts: 14,981
Default

No. 4
Attached Images
 
bigdawg is offline   Reply With Quote
Old Nov 11, 2007, 8:30 PM   #50
Senior Member
 
bigdawg's Avatar
 
Join Date: Feb 2005
Location: Thach Alabama
Posts: 14,981
Default

No. 5
Attached Images
 
bigdawg is offline   Reply With Quote
 
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -5. The time now is 8:17 PM.