Sunday, 26 October 2014

Using Auto ISO

We have been taught that Auto ISO is evil.  But is it?  If you know how to use it correctly, it can be used for the force of good! ;)

The Nikon D610 (and of course, many other cameras) has an Auto ISO feature which allows the user to set the maximum ISO it can go to and the minimum shutter speed to prevent camera shake.  I set the maximum ISO to be 6400 as the quality at that ISO for Nikon D610 is still acceptable to me.  As for minimum shutter speed, I leave it at the middle of Auto, which will ensure the shutter speed does not fall below 1/focal length of the lens I am using.  I can vary it by up to 2 stops if for instance I am using Vibration Reduction lenses, or I can just manually select a shutter speed as slow as 1s.

The Auto ISO feature really shines when you are shooting wildlife esp. birds.  A typical scenario will be using shutter priority to set your shutter speed to say, 1/2000s, and the camera will first ensure the lens is wide open before boosting the ISO.  Exposure compensation will work as normal as well, so for example if you are shooting a bird in flight against a bright sky, you may +1 or 2 EV and the ISO will also increase accordingly (assuming aperture already wide open).

But what if you don't want to shoot at wide open aperture?  Take my Tamron 150-600mm as an example.  It is sharper at f/8 than f/6.3.  So if there is sufficient light, I would very much prefer to shoot at the former rather than the latter.  But you can't do that in shutter priority as the aperture is not controlled by you.  Although you can do it in aperture priority, you have to be careful of your shutter speed, and to make things worse, any exposure compensation will affect the shutter speed.  So this is not ideal for birding.

However, this is where shooting at manual mode comes to the rescue.  Simply set your desired shutter speed e.g. 1.2000s and aperture e.g. f/8 and enable Auto ISO.  When performing exposure compensation, the ISO will automatically increase or decrease accordingly.  Voila! :)

The last thing to note is to always manually set your ISO to the lowest you desire e.g. 100 before enabling Auto ISO.  This does not affect manual mode, but if you are on aperture or shutter priority, that ISO you set will automatically become the floor of your Auto ISO.  In other words, if you set it to be 3200, then you will always shoot at ISO 3200 or higher no matter the lighting condition unless you are in manual mode.

Monday, 20 October 2014

Lightning to SD Card Camera Reader

I bought the Lightning to SD Card Camera Reader recently so that I can copy images from my SD cards into my iPad.  The main reason for doing that is to act as a backup for my images since I may not want to bring along my laptop especially for short trips.  A secondary reason is to be able to view and edit images, although this is not as critical. 

There are actually other devices out there that can backup images out field e.g. NEXTO DI ND2901 but they do not come cheap.  I also wish to make use of existing devices I have as far as possible.  Since I already have an iPad and chances of me bringing it along for trips is high especially when I don't want to bring along a laptop, it makes sense to leverage on the iPad rather than buy something new.

As for getting images into the iPad, there are other ways besides using the card reader such as Wi-Fi.  The problem is I shoot RAW, and transferring RAW files over the air is not only agonizingly slow, it gobbles up battery power for lunch too.  I would imagine wireless transfer would be useful for scenarios where you want to shoot and have the pictures (preferably JPEG for faster transfer) immediately available on the iPad for you or your client to review.  But since my primary objective is just to backup the SD cards, I don't really need the wireless option.

The iPad can import RAW files using the iOS 8 Photos app, but it is slow in displaying the images and this seems to be a bug introduced in iOS 8.  Hopefully it will be resolved in the latest iOS 8.1.  I just imported 315 NEF files (20.2GB) from a SanDisk Extreme Pro 32GB SDHC UHS-1 to an iPad Air running iOS 8.0.2 and it took around 19 mins and consumed 4% of my iPad's battery. 

What about getting the images off the iPad and into the computer?  If the iPad is solely used for backup and nothing else, and the original SD cards are untouched, then you can simply ignore the images on the iPad and import directly from the SD cards.  Once the import is successful, you can delete the backed up images from the iPad to free up space using utilities like Image Capture on your Mac. 

For users of Adobe Lightroom mobile, you may be aware of the auto import feature that will automatically add new images in your camera roll into Lightroom.  Unfortunately it will not do so for RAW files so I cannot use that to import the files into Lightroom.

However, the iPad can do more things than simply act as a backup device; you would probably want to view and edit those images you shot with your camera on your iPad.  The Photos app in iOS 8 is able to display and "edit" RAW files.  I use it to go through the images on my iPad and delete unwanted ones.  Thereafter I use Lightroom to copy directly from the iPad rather than the original SD cards.  It is probably slower this way but at least I can avoid importing unwanted photos.  It's a pity labelling certain images as favourites in Photos will not port over to Lightroom.  Perhaps if I import from Photos to iPhoto on my Mac then export from iPhoto to Lightroom, it may work.  But it's too much a hassle, honestly speaking. 

Last but not least, the card reader only works on iPads and not iPhones.  If intended purely as a backup device, the iPhone, being smaller, is obviously more suitable than iPad, assuming same storage capacity.  And with the new iPhone 6 Plus, the screen has gotten bigger to facilitate viewing and editing, if necessary.  I will almost always walk around with my iPhone but not iPad.  iPad Mini is an option, but again, it is not a device I will always walk around with.

Sunday, 12 October 2014

How to clean your camera sensor

Once you realise your camera has sensor dust, what do you do about it?  Well, you should clean it to save yourself a lot of grief in post processing later.  Most cameras nowadays have a built-in sensor cleaning feature which basically shakes the sensor during power on and off in an attempt to remove the dust.  But if your camera still have sensor dust despite this feature, then you need to adopt more drastic measures.

The easiest option is simply remove your lens (and switch your camera if DSLR to sensor cleaning mode to raise the mirror and open the shutter) to expose the sensor and use a rocket blower to blow air onto the sensor, hopefully knocking off some of the dust particles.  This is not the most effective option but it is doable by anyone.

The second option requires you to use a sensor swab to wipe your sensor.  Not all users are comfortable doing this by themselves.  In that case, just send your camera to your trusted camera store or service centre and have the technicians there do it for you.  Previously I sent in my Sony NEX-6 to the Sony Service Centre for sensor cleaning.  The turnaround time was around a week but it was free of charge as my camera was under warranty then.  It's a pity that Nikon does not offer free sensor cleaning for its camera under warranty.  So I try to take advantage of free sensor cleaning opportunities during Nikon events.  For example, I recently attended a Nikon event and you can see the pictures below showing my Nikon D610 sensor before and after cleaning:

Before sensor cleaning
Before sensor cleaning: there were many dust particles, particularly along the left edge.
After sensor cleaning
After sensor cleaning: only 1 or 2 dust particles left.

Friday, 3 October 2014

How to use both self-timer and MUP on Nikon D610

The beginning photographer learns quickly that the self-timer is very handy to avoid touching the camera when the remote shutter release is not available.  The remote shutter release is still useful for situations where timing is critical e.g. fireworks but one can never forget to bring along the built-in self-timer. ;)

However, things become a little bit more complicated when dealing with DSLR.  DSLR has a mirror which also causes vibration and hence most DSLRs have a mode called MUP for mirror lock-up to reduce camera shake.  For obvious reason mirrorless camera does not have the same issue.

Can the photographer combine both self-timer and MUP?  It is not possible on my Nikon D610 as the self-timer and MUP are separate items on the mode dial.  I heard that it's possible on Canon though.

However, there's a workaround -- by using the Exposure Delay menu option (d10).  This introduces a delay of up to 3s after the mirror goes up.  So I can turn the mode dial to self-timer mode and set the timer to be, say, 2s.  Once I press the shutter release, the timer will countdown 2s and the mirror will flip up.  After 3s then the shutter will open and the picture taken.  The 3s exposure delay will hopefully negate any vibration caused by the mirror flipping up.

Last but not least, according to this workaround also works on the Nikon D750.