Canon EF 100mm f/2.8 Macro USM vs Tamron SP Autofocus 90mm f/2.8 DI Macro Lens

[hwchoy]

Wah... got $20 flash one ah... any pictorial diagram how the setup will look like?

If you use Av mode and let the cam decide your shutter speed, what happens if the cam chooses a much slower shutter speed?

with flash enabled, your shutter speed will be set to the x-sync speed which is typically 1/200 or 1/250s.

 

[Denosha]

Anything more than F16 is generally bad for sharpness because of diffraction effects. I guess it's a balance between how much DOF u really need and how much of a drop in quality you're ok with. As for the shutterspeed, you could always set it to as fast as your flash sync allows to minimize problems with hand shake (although at macro magnification, this problem becomes amplified).

Oh. And set your cam to full manual mode and set the aperture yourself. ISO and shutterspeed can pretty much fix it.

 

[yehosaphat]

with flash enabled, your shutter speed will be set to the x-sync speed which is typically 1/200 or 1/250s.

Do you mean in Av mode, just by setting aperture to say f16, the shutter speed will auto be set to the sync speed of 1/250?

 

[yehosaphat]

Do you mean in Av mode, just by setting aperture to say f16, the shutter speed will auto be set to the sync speed of 1/250?

Advise pls on the above?? And Do you need to set anything on the flash for high speed sync?

 

[mpenza]

Do you mean in Av mode, just by setting aperture to say f16, the shutter speed will auto be set to the sync speed of 1/250?

No. For Canon cameras using Av mode, by default, the camera will determine the shutter speed based on the scene it sees (so that the scene is properly exposed). So, if it's dark, the shutter speeds could be very slow and if it's very bright the shutter speeds will be clipped to sync speed (if high speed sync is not enabled and this will result in overexposure) or to the setting that allow proper exposure of the background (if high speed sync is enabled).

If you want the shutter speed to be auto set to sync speed using Av mode, you need to adjust a custom setting first (e.g. setting #3 for 30D: http://www.dpreview.com/reviews/canoneos30d/page10.asp ) But if you do this, you might as well use manual mode!!!

 

[Denosha]

In Av mode the shutterspeed will keep changing but the upper limit will be your flash sync speed (what it is depends what body you're using). If you want to use a shutterspeed higher than the sync speed then you have to set the high speed (or HS) mode on your flash.

Like I've said previously, there's no need to use Av mode. Just set the ISO, shutterspeed and aperture in manual mode, use the right metering mode and let the flash do the work.

 

[mpenza]

And Do you need to set anything on the flash for high speed sync?

Yes, you need to enable high speed sync on the flash, e.g. for 430EX, press the button between "Mode" and "Zoom": http://www.dpreview.com/news/0508/05082206canon430ex.asp .

 

[yehosaphat]

In Av mode the shutterspeed will keep changing but the upper limit will be your flash sync speed (what it is depends what body you're using). If you want to use a shutterspeed higher than the sync speed then you have to set the high speed (or HS) mode on your flash.

Like I've said previously, there's no need to use Av mode. Just set the ISO, shutterspeed and aperture in manual mode, use the right metering mode and let the flash do the work.

Ok... so set f16 and 1/200s that's all right?

What metering mode do you all use in macro photography

 

[yehosaphat]

Yes, you need to enable high speed sync on the flash, e.g. for 430EX, press the button between "Mode" and "Zoom": http://www.dpreview.com/news/0508/05082206canon430ex.asp .

For 420ex?

 

[Zplus]

For 420ex?

420ex got a dedicated switch to enable high speed sync.

 

[yehosaphat]

Yup... so just switch to the flash symbol with the H right?

I also read somewhere you should set your flash to the rear curtain when taking macro... is it true? IF so why?

 

[yehosaphat]

Anyone can advise on the above?

Also, what are the flash models you guys use for macro?

 

[mpenza]

I also read somewhere you should set your flash to the rear curtain when taking macro... is it true? IF so why?

don't think it really matters. the shutter speed is usually very short, so it doesn't make much of a difference whether front sync or rear.

 

[hwchoy]

I thought curtains are only important for moving subjects.

 

[ST_sg]

Anyone can advise on the above?

Also, what are the flash models you guys use for macro?

Due to fast shutter speed, I guess, there is no different between flash it while shutter open or at rear shutter. :think:

 

[astroboy]

I already have the EF 70-200IS so will most likely add on a T90 for the occasional studio macro work.

 

[Zplus]

Yup... so just switch to the flash symbol with the H right?

I also read somewhere you should set your flash to the rear curtain when taking macro... is it true? IF so why?

The difference is seen in the image when the subject is moving. The motion trail is behind the subject in rear curtain sync and in front of the subject when it is not. You can control that in the camera. Gotta read the manual to see how to set this. Dont have a pciture to show you but you can google it.

 

[yehosaphat]

Ok, thanks for the advises guys... you think it is necessary to upgrade from a 420EX to a 580EX for this purpose?

 

[Garion]

Ok, thanks for the advises guys... you think it is necessary to upgrade from a 420EX to a 580EX for this purpose?

Depends on what is your usage for the flash. 580EX is definitely more powerful. But for general macro, 420EX suffices. Just need to slap on a bounce card or Omnibounce and you're set.

 

[yehosaphat]

Thanks! Anymore great macro resources to share?