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 Jul 19, 2006, 8:04 AM   #11
Senior Member
 
nlp239's Avatar
 
Join Date: Jan 2005
Posts: 719
Default

Roy, no offence meant but, wouldn't these be close-ups as opposed to macro???

My lens says macro but it really isn't it is a closeup. There used to be a definition that macrography was anything closer than an inch. Now I don't know whether they meant from the lens to the subject or the size of the magnification.

Once again, no offence is meant. But I am getting very mixed-up.
nlp239 is offline   Reply With Quote
Old Jul 19, 2006, 8:23 AM   #12
Senior Member
 
thekman620's Avatar
 
Join Date: Feb 2004
Posts: 6,084
Default

Good shots Roy. Looks like you're quickly getting the hang of using the tubes. Takes lots of patience. Looking forward to seeing more.......cheers.....Don.
thekman620 is offline   Reply With Quote
Old Jul 19, 2006, 8:38 AM   #13
Senior Member
 
ennacac's Avatar
 
Join Date: Mar 2005
Posts: 4,198
Default

Extension tubes are a less expensive alternative to a macro lens that allows you to use your existing lenses for macro work. My set was a bit more expensive than Roy's since it has the electrical contacts for AF and f/stop setting on A lenses, but other than that they all work the same. Since they don't have any lenses in them, any version you chose will do the job the same optically since that depends on the lenses you use not the tube set.

It has been between 100F and 93F for over a week now but today we are possibly getting some rain and lower temps which we need both of.

Tom
ennacac is offline   Reply With Quote
Old Jul 19, 2006, 9:20 AM   #14
Senior Member
 
ennacac's Avatar
 
Join Date: Mar 2005
Posts: 4,198
Default

Took this this morning (nice and cool, 70F, but no sun) with the same setup as last night, 200mm lens, with 68mm tubes at 125/sec, f/2.8.



Tom
ennacac is offline   Reply With Quote
Old Jul 19, 2006, 10:36 AM   #15
Senior Member
 
ejbrusselsprout's Avatar
 
Join Date: Feb 2006
Posts: 137
Default

nlp239,

hope you don't mind my two cents....

i've read several definitions of "macro" one of which was just "focussing closer than a lens (of whatever focal length) normally would". so you see lots of zooms that are called "macro" even though they don't go to a 1:2, they maybe go to 1:3.5 or 1:4.

i've also seen "true macro" defined as going to at least 1:2 without extension tubes.



nadnerb,

the ratios just refer to the size of the image on the actual sensor or film frame, so a lens that will do 1:2 will (at its closest focussing distance) put a subject on the sensor at 1/2 life size. it's important to remember we're talking about the size on the sensor since the printed image can be whatever size you choose.

another way to say it; the ist dl sensor is 23.5 mm wide. a lens that does 1:2 (half life size) will fill the frame side to side with a subject 47 mm across. one that goes to 1:1, a subject 23.5 mm across, etc.

personally i only use the magnification numbers when looking at lenses i might want to buy. my sigma 70-300 goes to 1:2 which was a factor when i bought it, but when using it i never think about it, just compose and shoot and use the macro function or add ex tubes to get the image i want. here's one i took at 300mm on macro but no additional tubes. no idea what magnification:

i see i've gone on pretty long so better quit.

all the best and hoping i haven't muddied the water, eric
Attached Images
 
ejbrusselsprout is offline   Reply With Quote
Old Jul 19, 2006, 10:58 AM   #16
Senior Member
 
ejbrusselsprout's Avatar
 
Join Date: Feb 2006
Posts: 137
Default

hi again,

roy, forgot to say appreciate the pix. i did a similar shot of a brass caliper when ifirst got my 70-300 just to see how it compared with my s602. it only does macro at 300mm which gives a lot of working distance which is usually nice but on my "lens list" is a shorter macro or just a shorter lens with aperture ring i can use with the tubes for when i don't have much working room or want more of the backround in the shot.

tom, i like the flower, is it a blanket flower? we had them in northern b.c. but i don't think i've seen them here.

on a tripod i almost always use the 2 sec. delay with mirror lock-up like you said. makes a big difference esp with the long lens. another nice feature on a "consumer grade" camera!
ejbrusselsprout is offline   Reply With Quote
Old Jul 19, 2006, 10:59 AM   #17
Senior Member
 
Monza76's Avatar
 
Join Date: Jul 2004
Posts: 4,093
Default

I have a Takumar-A 2X teleconverter, or should I say had? I just unscrewed the lens package (darned if it didn't come out as a unit so it can be replaced later. This gives me an auto-exposure extension tube of about 26mm, along with my m50mm f1.7 and some close up lenses I should get pretty close now.

Ira
Monza76 is offline   Reply With Quote
Old Jul 19, 2006, 11:54 AM   #18
Senior Member
 
nlp239's Avatar
 
Join Date: Jan 2005
Posts: 719
Default

Eric, I don't mind at all - all info counts and I am here to learn. Just hope Roy doesn't get angry for highjacking his thread.

I think the point I was making was better answered in your reply to "nadnerb". The macro function of the 70-300 is at 1:2 but it isn't really macro is it?

Forgive me for being so thick-headed.
nlp239 is offline   Reply With Quote
Old Jul 19, 2006, 12:06 PM   #19
Senior Member
 
Monza76's Avatar
 
Join Date: Jul 2004
Posts: 4,093
Default

Here is a shot from my newly modified Takumar-A "extension tube", taken with the 50mm f1.7 M at about f8. This shot is straight from the camera, just resized.

Ira
Attached Images
 
Monza76 is offline   Reply With Quote
Old Jul 19, 2006, 12:30 PM   #20
Senior Member
 
ennacac's Avatar
 
Join Date: Mar 2005
Posts: 4,198
Default

Took this today hand held with the 200mm and 68mm tube, hand held at 2.8, but the shallow DOF made for a strange looking bird.



Tom
ennacac 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 3:53 AM.