wich focal lenght for macro lens on aps-c sensor or ext tubes for my 18-125

[jalcocer]

Hi, well, being a year since I started with photography and have to say I've learned a lot, and most of it thanks to this site. Started with nikon but it failed and finished with the store giving me a canon instead (odd but true) and at the moment get a 50 1.4 and a 18-125 for all around photography, both sigma and have to say very good indeed.

Since I don't get a chance to shoot outside that much (really dangerous to go out with a camera over here) I decided to focus more on my portraits indoors and since a while back I been wanting macro in products, or maybe some staged scenes with still life, water tanks, toys, etc., so my question is this, i'm close to have enough for a true macro lens, I'm going with sigma again, but I don't know which focal lenght should be better for me, there is a 70 2.8 macro and a 105 2.8 macro both at similar price point, so my real problem is which one to choose, is the 70 going to be to little for what I want or is the 105 going to be too much, also lets take into account I'm using aps-c sensor so it's 70*1.6 or 105*1.6 (using canon).

The other is go for a set of extension tubes (which I can get right away) and get more juice out of my 18-125 and go for other accesories that may be useful for my indoor shooting.

Oh boy, there are so many choices, but it is really good to have this place to find good pointers and recommendations.

Just for the record, the kind of set up scenery with toys I would like to accomplish are like these ones:

http://fstoppers.com/proof-that-great-photography-has-little-to-do-with-your-wallet

[luxborealis]

My preference has always been for a true, fixed focal length (prime) macro lens - the longer the better. A longer focal length gives you greater working distance between the end of the lens and your subject. Having that extra working distance makes lighting far easier for inanimate objects such as you wish to do. It is also a more comfortable working distance for animate objects like insects, frogs, etc. that won't tolerate a shorter working distance.

Given your decision, I would recommend the 105mm. However...the 150mm Sigma would be even nicer to work with and is about $100 more than the 105mm. Again, greater working distance is the key, especially with lighting, both artificial and natural as in both cases there is more room for reflectors as well as main light source.

Using extension tubes on your current zoom will work - and will work fairly well especially zoomed to 120mm to get that greater working distance - but will not have the sharpness and contrast of using a true macro lens which is specifically designed for closer focus. If you have the money and want to "go macro" then saving for the 150mm would be option 1, I would think; the 105mm would be option 2. Without testing optics, you might find that your current zoom with extension tubes will perform almost as optically well as the 70mm but at a slightly greater working distance. Of course, it's also important to consider that given the nature of your photography and where you wish to go with photography it might make it difficult to justify the additional cost of a macro lens over extension tubes.

Photography is a trade-off: higher quality mean greater cost. I alway advocate saving for the best you can afford. But, if you are paying for quality that you will never really use, then maybe it's money you don't need to spend.

[jalcocer]

Well I guess I can try first with the extension tubes and see what kind of pictures I can come up with, I know won't be the same quality as you say but could be a good start point to see if this kind of photography suits me well and if it's something I'd like to do on regular basis, and then if that happens, go for the real deal, either the 105 or the 150, and besides I guess one of those can also help out with some portraits to complement my 50mm. The tubes are really cheap so I can start there with no impact on my wallet and continue saving for a real macro, and if at the end this is not my cup of tea, well, I'll still have money to invest on another lens or equipment.

thanks for the quick response, I've read some of your post and answers to other members and found your feedback really useful.

[luxborealis]

jalcocer,

Be wary of "really cheap" extension tubes as they may not hook up electronically with your digital camera even if they are called "Auto" extension tubes. This may mean loss of autofocus and loss of aperture control. A good set of electronically-coupled extension tubes will be a few hundred dollars. The cheapest I can see are a set of three electronically-coupled tubes for $180 (e.g. bhphoto - http://www.bhphotovideo.com/c/search?Ntt=canon+extension+tubes&N=0&InitialSearch=yes)

--Terry

[jalcocer]

Well I was thinking on the canon set the ones with the contacts for controlling aperture and the focus confirm, still 180 for the set of three vs. 1000 for the 105mm or 1100 for the 150mm is a huge difference in price just to get the feeling of it. I know about the cheap tubes and no focus confirm and no aperture control, already know the tricks for that but still the canon set is way better choice. 

Thanks again for taking the time to answer, I really appreciate it.

[Tony Jay]

Have to agree with the comments so far:
A dedicated macro lens of around 100 mm is the way to go.
Extension tubes that allow the camera to talk to the lens are essential.

Further thoughts:
A 100 mm macro lens makes for a fantastic portrait lens as well.
If you really want to pursue macro photography you should investigate focus stacking as a technique.
Both CS5 and Helicon focus have the ability to do the requisite merging.

Regards

Tony Jay

[jalcocer]

thanks for your comments, I'll look into all of this you are telling me, by the way, found a good deal on the sigma 105mm macro without OS, don't need image stabilization since I'm setting up the lighting, and the price is around 480 dls, half the price of the new 105.