[meigloo]

hello everyone
I'm totally new on this field and there is somth which is not really clear for me for now.
What is the difference between 35mm Macro and 100mm Macro, please? Why would i choose one or another if i want to do only Macro photos?

Thank you!

[Aristophanes]

You can get much closer with the 100mm.

The DA 35 I call a walkaround macro. Really good for the occasional close-up, leaves, flowers, rust. It's 35mm focal length makes it easier to handhold at a reasonable shutter speed.

90-105mm macros can get very high magnification on the subject. Think bug's eyes. But they often require a tripod and auxiliary lighting because at the focal length they need a faster shutter speed.

For dedicated macro work, longer is better. It depends on your subject matter. If you were doing macros of, say, buttons for a clothing store, the DA 35 would be fine.

Check out the Pentax Gallery for examples, and, of course, Flickr.

[meigloo]

Thank you, Aristophanes! now makes sense

[Kozlok]

Both macros have 1:1, so the first answer is actually incorrect. Both will give you the same magnification. They have different angles of view, though. Assume that you compose a picture of the same subject with each lens with the main subject at the same size. The 35mm lens will have to be much closer to the subject to achieve this.

Also, the resulting pictures will be different in that the background objects will appear smaller and farther away with the 35 vs the 100, and you will be able to see a wider view of the background with the 35 vs the 100.

The Wikipedia article on angle of view is pretty good at showing the difference in compositions with different focal lengths:

Angle of view - Wikipedia, the free encyclopedia

[VisualDarkness]

Yep, both go to 1:1 which means that the image projected on the sensor, when the lens is focused at its closes, is the same size as in real life. So if an ant is 3mm it will be projected as 3mm on the sensor.

[Bob from Aus]

You can get much closer with the 100mm. The DA 35 I call a walkaround macro. Really good for the occasional close-up, leaves, flowers, rust. It's 35mm focal length makes it easier to handhold at a reasonable shutter speed.

This is a bit confusing both macros go 1:1
The 100 macro you are further back (about three times) for the same size frame.
Pentax has a number of 35mm. The 35 you are talking about I believe is called a 35Ltd macro not to be confused with other 35mm lenses.

If you want to photograph insects, then the 100 mm will allow give you a better chance to get your photo because you are further away. The closer you get the higher the chance it will escape,

The 35mm has much greater depth of field and it is much better for things like wildflowers. The 35mm is also more versatile and if you don't have many lenses it really is an excellent one to have. I am a bit greedy and have over 20 lenses. my 35mm ltd is usually the first lens to go into my bag.

[meigloo]

Both macros have 1:1, so the first answer is actually incorrect. Both will give you the same magnification. They have different angles of view, though. Assume that you compose a picture of the same subject with each lens with the main subject at the same size. The 35mm lens will have to be much closer to the subject to achieve this.

Also, the resulting pictures will be different in that the background objects will appear smaller and farther away with the 35 vs the 100, and you will be able to see a wider view of the background with the 35 vs the 100.

The Wikipedia article on angle of view is pretty good at showing the difference in compositions with different focal lengths:

Angle of view - Wikipedia, the free encyclopedia

this is the dot on the i !!!
"Also, the resulting pictures will be different in that the background objects will appear smaller and farther away with the 35 vs the 100, and you will be able to see a wider view of the background with the 35 vs the 100.

Thank you so much! Now i even can see different the lenses...understand in perspective . ..So definitely 35mm is what i was looking for

[JohnX]

It's really all about working distance from the subject, as both offer 1:1 magnification. Working distance is the distance from the front of the lens to the subject.

You'll need to be close with the 35, so ideal for static objects - models, stamps, still-life flowers indoors, etc.

The 100 is better for live subjects - insects, flowers outside, etc - as the working distance is greater.

[VisualDarkness]

This is a bit confusing both macros go 1:1
The 35mm has much greater depth of field and it is much better for things like wildflowers. The 35mm is also more versatile and if you don't have many lenses it really is an excellent one to have. I am a bit greedy and have over 20 lenses. my 35mm ltd is usually the first lens to go into my bag.

The depth of field part isn't true, it is mainly depending on magnification not focal length. Though the perspective will blur out the background with the longer focal length than the shorter, the depth of field will stay the same at the same magnification.

[Bob from Aus]

The depth of field part isn't true, it is mainly depending on magnification not focal length. Though the perspective will blur out the background with the longer focal length than the shorter, the depth of field will stay the same at the same magnification.

Sorry I have no idea what you are talking about. The smaller the focal length for a given aperture the greater the depth of field. I use small point and shoots to maximise the opportunity for greater depth of field because the lens will be about 6mm.

Need a couple of other people to contribute and get the basics right as we are going to confuse our newbie

[VisualDarkness]

Sorry I have no idea what you are talking about. The smaller the focal length for a given aperture the greater the depth of field. I use small point and shoots to maximise the opportunity for greater depth of field because the lens will be about 6mm.

Need a couple of other people to contribute and get the basics right as we are going to confuse our newbie

Well, when you use small point and shoots you essentially have a cropped view and therefore either use a wider focal length or back off a lot to get the same angle of view. This results in a lower magnification as the ratio between the real sized subject and the image projected on the sensor will be less than 1:1 (the 3mm ant will be projected smaller on the sensor) . Use two different sensor sizes at the same magnification and see for yourself.

Read this: Understanding Depth of Field in Photography

[VisualDarkness]

If you use the same lens at the same distance (the same magnification) to the subject but on two different sized sensors the image in only cropped. The same image is possible to get by cropping the image from the larger sensor, if the sensor resolution holds up.

[VisualDarkness]

To the original poster.

The first difference is the working distance from the subject. For the 35mm to get to 1:1 magnification the subject will almost touch the front element. With the 100mm you will have a lot more distance to the subject for the same magnification.

The second difference is the perspective. With the 100mm the things in the background will appear larger than with the 35mm as a wider angle compresses things farther away. The wider lens will capture the scene at a wider angle so more of the background scene will be compressed in compared to the 100mm.

[tclausen]

To the original poster.

The first difference is the working distance from the subject. For the 35mm to get to 1:1 magnification the subject will almost touch the front element. With the 100mm you will have a lot more distance to the subject for the same magnification.

The second difference is the perspective. With the 100mm the things in the background will appear larger than with the 35mm as a wider angle compresses things farther away. The wider lens will capture the scene at a wider angle so more of the background scene will be compressed in compared to the 100mm.

So, I want to +1 to the above two, and then add a third observation....

A lot more distance-to-the-subject can be a mixed bag, a curse as well as a blessing.

If you're trying to photograph something venomous and/or with claws (such as a mother-in-law), then being at a distance may be a blessing.

However, on a warm summers day, the movement of rising hot air may actually cause disturbance in the image - the longer distance-to-the-subject, the more "hot air" will there be between your camera and your subject, and the "more magnification" the more will such movements degrade the image quality.

So, I guess that the LBA answer is, that you will need both

[Bob from Aus]

hello everyone I'm totally new on this field and there is somth which is not really clear for me for now. What is the difference between 35mm Macro and 100mm Macro, please? Why would i choose one or another if i want to do only Macro photos? Thank you!

So if you are still reading this confusing thread with all the mumbo jumbo the 35mm lens will provide a lot more depth of field compared with the 100mm. Why exactly is not really important.