BetterPhoto Q&A
Category: Macro Photography Tip

Mike Stephens

Close-up Help!

I'd like to take extreme close-up shots (flowers, insects, etc.). I just bought a Tamron Macro 100-300mm lens for $80, but either it is the wrong lens for what I want to do since objects appear way out of focus or I'm doing something wrong. PLEASE help!! I tried the Internet and seem to get all advanced sites and no real answers.
Thank you so much!!

To love this question, log in above
July 01, 2005

Mikki Cowles

With a 100-300 lens, you cannot get too close - a minimum focal distance may be from 3-8 feet away. This is good if you are trying to capture some flighty insects, but if you want to be physically close to your subject with a lens like this, you need an extension tube. Then you are looking at just a few inches.

To love this comment, log in above
July 01, 2005

Mike Stephens

Thanks, Mikki. OK ... so what's an extension tube? And do I need a specific one to fit the camera and lens I have?(Tamron Tele-Macro 100-300mm lens on a Maxxum-5 SLR.
Thank you again =)
Mike

To love this comment, log in above
July 01, 2005

Andy

Please take a look here for information about extension tubes:
http://www.thkphoto.com/products/kenko/slrc-04.html
You need to get the one that is for Minolta lens mount. Anyway, the word "macro" on the Tamron lens is somehow misleading. Hope this helps.

To love this comment, log in above
July 02, 2005

Irene Troy

Hi Mike -
Okay, here is what I know about macro and specifically about Minolta lenses for macro work. First, if what you want to do is real macro (close-ups of flowers, insects, anything really close), you will most likely be happier with a fixed length (prime) lens. I can recommend either the Tamron 90mm or the Minolta 100mm Macro. I own the Tamron 90mm, and it is a good lens. However, if I do it again I will go for the Minolta lens. There is, of-course, a price difference. If you only do occasional close-ups, you might consider the Minolta 50mm lens. This is a fairly versatile lens – some people call lenses such as this one an “all-purpose” lens because you can do some macro with it and also use it for many other purposes. What I think you should look for when purchasing a lens to do macro work with: a lens capable of being opened up to f/2.8 (large apertures are essential for clarity and sharpness with macro work); a lens that will produce true 1.1 ratio; and, of course, good optics – which is probably why the Minolta lenses are better than the Tamron ones.
Extension tubes: I have a set of Kenko extension tubes that I purchased from B&H photo for $129.00. http://www.bhphotovideo.com
BTW: the lens you purchased on eBay is an okay lens, especially for the price. Unfortunately, it will not help you very much if you want to make macro images. But, if you are trying to capture something at a distance, it will serve fairly well. Good luck and keep coming back!

To love this comment, log in above
July 02, 2005

Bob Cammarata

Mike,
If your subject is "way out of focus", with the lens you have ... you need to move in closer. Even though the Tamron 100-300 isn't a true macro lens you should still be able to focus close. Turn the lens to its closest focusing distance ... (the lens barrel should be fully extended.)
Then move the camera and lens toward the subject while looking through the viewfinder. You will see the subject pop into focus when you've gotten close enough.
(Note: A newspaper or other printed page is good to use for this simple test. When you can read the print clearly through the viewfinder, you've reached the minimum focusing distance of that particular lens.)
As far as true macro capabilities, Irene and Mikki are correct in that a prime "macro lens" - and/or extension tubes - will help to achieve true life-size reproduction.
What Andy referred to as "misleading" is that many lens manufacturers will slap the word "macro" or "macro-capabilities" on their close-focusing lenses. The thing to watch for is the life-size reproduction they claim to achieve. True macro lenses can achieve 1:1 (life size) ... or at least 1:2 (1/2 life size).
Your lens probably gets to 1:4 (1/4 lifesize) or 1:5, but I couldn't find any specs on your lens to verify this.

Even so, you still should be able to focus at whatever minimun distance your lens will allow.

To love this comment, log in above
July 02, 2005

Mike Stephens

Andy, Irene, and Bob: Again, THANKS for the help and suggestions. For now, I did get a tripod and a ND-filter (and a UV & star filter). I have a lot of research to do b/c all these terms of "Macro", "Extension Tubes", ratios, etc. is a bit confusing for me. I used the new lens today and will post the pics when I get them developed in the next day or two.
But allow me to clear my question up--The BEST and most economical way for me to take SUPER close-ups would be with extension tubes. But using WHICH of the two lenses I have...the Minolta 28-100 or the Tamron 100-300?
mike

To love this comment, log in above
July 02, 2005

Scott W. Pierson

Mike,

Here's the answer you're looking for. The difference between the two lenses you have will probably the minimum focal distance, which is how close you can get to something and have it still focus. I have a 100-500 lens with macro but the minimum focal length on it is 39 inches. I also have a Sigma 28-200 lens with a minimum focal range of 12 inches.

Since I can be 3 times closer with the 28-200 lens, I can actually take more magnified pictures with the 28-200 lens.

Adding an extension tube to the 28-200 allows me to focus at about 6 inches. (The new focal range depends on the length of the tube.) However, with the extension tube there is a trade off and that is I can only focus extended out from 120-200mm of the 28-200 range.

I also have a doubling adapter that adds a 2x magnification that I put closest to the camera body, then the extension tube followed by the lens. This pushes out the minimum focal length slightly and reduces the zoom ability even more, but with this combination I can fill the frame with a flower that is less than an inch in diameter.

So to answer your question, which lens will work best depends on how close you want to get to your work versus how much magnification you want. Always look at the minimum focal length when you purchase a lens.

The Tamaron lens looks like it goes from a 4.9 foot minimum focal length to 3.1 (39") feet in macro. The best I can tell, your minolta lens has a minimum focal length of 18 inches, which means that it is equivolent to 200mm on the tamaron. menaing that you can get more magnification from your tameron lens, but you have to be further from your subject.

Scott