Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
10-13-2009, 04:57 PM   #1
Pentaxian
adwb's Avatar

Join Date: Sep 2009
Location: Bristol UK
Photos: Gallery
Posts: 1,631
50mm vs 100 mm for macro?

Hi I need advice from those wiser than me , which is plenty of you!!
I have a kit 18-50 A/F lens supplied with my camera which is fine for close up images of flowers and other large object that don't get frightened by a lens looming in at them.
But I would like to try to capture insects, spiders and ladybirds and the like which are small and need a 1:1 macro or better, or so I understand.
It seems since I cannot afford a new 1:1 macro lens that I have choice.
Get an A series 50mm 2.8 [which I understand from another post is better than the 1.4 for this due to the construction] and try it with an extension or reversing ring both of which I have, these 50mm seem to be plentiful and cheap from various sources, or
to wait and try to find A series 100mm macro which will allow some distance to be maintained from the insect ,
comments , thoughts , and advice please as I really can't afford to buy lenses that won't do the job.
Alistair

10-13-2009, 05:43 PM   #2
Pentaxian
Wheatfield's Avatar

Join Date: Apr 2008
Location: The wheatfields of Canada
Posts: 10,043
A 50 on an extension tube is an OK macro combination. The major constraint, of course, is somewhat fixed reproduction ratios due to the stepped extension.

OTOH, you can still use the focus ring, so that helps quite a lot.

It is also nice to be able to remove the tube and have a nice, fast 50mm lens for portraiture and short telephoto work.

Any macro lens in the 90-100mm range will be nicer to use, and they pretty much all are good, no matter what brand or speed or focus type.

The longer focal length gives more working distance. Your zoom lens probably macros at it's longest focal length, so you are already familiar with the constraints that a short working distance gives.

So, for myself, I'd go out and get a real macro lens that is ~100mm focal length, and at some point, pick up a 50mm lens for other stuff. Don't worry about if it's AF or not, auto focus is highly overrated for macro, as most focusing is done by physically moving the camera backwards and forwards.
10-13-2009, 06:52 PM   #3
Veteran Member
Fixcinater's Avatar

Join Date: Jun 2009
Location: San Diego, CA, USA
Posts: 409
I shot this with a relatively cheap Super Takumar 135mm f/3.5 with ~50mm of extension tubes. Way better working distance with a telephoto.


I shot this with a relatively cheap Super Takumar 55mm f/1.8 with ~145mm of extension tubes (every one that I have). Slow shutter, handheld, f/1.8, ISO 3200.


Just showing what kind of magnification you can get with a ~50mm.



Hope this helps some...
10-13-2009, 06:59 PM   #4
Ash
Community Manager
Loyal Site Supporter
Ash's Avatar

Join Date: Mar 2007
Location: Toowoomba, Queensland
Photos: Gallery | Albums
Posts: 22,678
Allistair, welcome.
Indeed the extension tubes hooked onto a relatively long lens give you that extra working space and reaslonably good results, so that may be your solution.

Or even consider the Raynox attachment (examples are here: https://www.pentaxforums.com/forums/pentax-slr-lens-discussion/74221-raynox-macro-club.html)

All the best for that.

10-13-2009, 07:44 PM   #5
D W
Veteran Member




Join Date: Mar 2008
Location: Hogtown, ON, Canada
Posts: 329
if you are shooting insects etc it would be a good idea to use longer focal length.

A dedicated macro lens is handy but you can get good result with extension tube or a good quality close up lens which screws onto the main lens like a filter.

At such high magnification manual focus is the way to go to pick the exact area you want.
10-14-2009, 01:18 AM   #6
Veteran Member




Join Date: Jan 2009
Location: Budapest
Posts: 821
QuoteOriginally posted by adwb Quote
to wait and try to find A series 100mm macro which will allow some distance to be maintained from the insect ,
I have a Pentax A 100mm F4 macro lens and I like it. It allows to shoot insects from a comfortable distance, so it doesn't scare them away. Last weekend I was shooting bees and bumblebees on flowers and it was great to shoot them from some distance. Max magnification is only 1:2 of this lens though. Later I might buy extension tubes or a Raynox to get 1:1 or higher magnification.

QuoteOriginally posted by Wheatfield Quote
Don't worry about if it's AF or not, auto focus is highly overrated for macro, as most focusing is done by physically moving the camera backwards and forwards.
I second that. My lens doesn't have AF and I don't miss it for macro. I just turn the focusing ring all the way to closest distance to get 1:2 magnification and then move the camera forth and back "to focus".
10-14-2009, 01:30 AM   #7
Veteran Member




Join Date: Jul 2009
Location: Russia
Posts: 341
Another way is to bay small and cheap reverse adapter.
As far as I remember you'll get about 1:1 ratio with normal 50mm lens
and about 2:1 ration with 28mm.
And I also suggest macro rails.
Also useful thing is to have cheap macro zoom like 28-90mm 1:2 macro zoom.
It costs about $30-$40 only.
10-14-2009, 03:06 AM   #8
Forum Member




Join Date: Nov 2007
Location: Philippines
Posts: 63
I'll go for a 100mm to have a bit more working space... I've used a MF 50mm w/ extension tubes before and it was quite hard to nail shots (compared to a dedicated macro lens) unless you're using a tripod.

10-14-2009, 03:31 AM   #9
Pentaxian
adwb's Avatar

Join Date: Sep 2009
Location: Bristol UK
Photos: Gallery
Posts: 1,631
Original Poster
Thanks for the replies, it seems that the majority vote is for a 10mm macro or with a macro adaptor of some type.
Ash thanks for the Raynox suggestion, I am aware of add on lenses for wide and tele enhancement but that brand especially for macro.
given all my lenses are tele lenses this might be the best route.
I have posted a question on the raynox thread you linked to about this
thanks you
Alistair

https://www.pentaxforums.com/forums/pentax-slr-lens-discussion/74221-raynox-m...tml#post774078
10-14-2009, 08:40 AM   #10
Veteran Member
troyz's Avatar

Join Date: May 2008
Posts: 389
QuoteOriginally posted by adwb Quote
given all my lenses are tele lenses [an add on lens] might be the best route.
What teles do you have? A longer lens + a weak close up lens will give you more working distance (for a given magnification) than a shorter lens + a stronger close up lens like the raynox 150 (4.8 diopter, working distance ~ 20cm) or 250 (8 diopter, working distance ~12cm).

The hard part is finding good two-element close-up lenses -- they're more expensive and harder to find than the crummy 1-element variety. (FWIW the two-element Minoltas are pretty good).

Another option would be a Cosina/Phoenix/Vivitar/Promaster 100mm/3.5 macro -- goes down to 1:2 magnification by itself but goes to 1:1 with a "matched" close up lens. It's very lightweight and economical (flimsy and cheap).

Cosina AF 100mm f/3.5 macro (Pentax) - Lab Test Report/Review
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
50mm, 50mm vs, advice, k-mount, lens, macro, pentax lens, series, slr lens
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
For Sale - Sold: Sigma 100-300mm f4 & 105mm f2.8 macro, Tamron 17-50mm Fl_Gulfer Sold Items 9 10-27-2010 10:56 AM
Pentax 100 WR macro vs Sigma 105 macro GSk Pentax SLR Lens Discussion 7 03-22-2010 04:23 PM
Is the Pentax-F 50mm 2.8 macro basically the same as the FA 50mm 2.8 macro? m42geo Pentax SLR Lens Discussion 7 11-23-2009 04:28 PM
D-FA 100/2.8 Macro vs other macro lenses? jankok Pentax SLR Lens Discussion 12 10-25-2007 09:01 AM



All times are GMT -7. The time now is 01:03 PM. | See also: NikonForums.com, part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top